1 /* 2 * Copyright (c) 2001, 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_G1_G1COLLECTEDHEAP_INLINE_HPP 26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP 27 28 #include "gc_implementation/g1/concurrentMark.hpp" 29 #include "gc_implementation/g1/g1CollectedHeap.hpp" 30 #include "gc_implementation/g1/g1AllocRegion.inline.hpp" 31 #include "gc_implementation/g1/g1CollectorPolicy.hpp" 32 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp" 33 #include "gc_implementation/g1/heapRegionManager.inline.hpp" 34 #include "gc_implementation/g1/heapRegionSet.inline.hpp" 35 #include "runtime/orderAccess.inline.hpp" 36 #include "utilities/taskqueue.hpp" 37 38 // Inline functions for G1CollectedHeap 39 40 inline AllocationContextStats& G1CollectedHeap::allocation_context_stats() { 41 return _allocation_context_stats; 42 } 43 44 // Return the region with the given index. It assumes the index is valid. 45 inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrm.at(index); } 46 47 inline uint G1CollectedHeap::addr_to_region(HeapWord* addr) const { 48 assert(is_in_reserved(addr), 49 err_msg("Cannot calculate region index for address "PTR_FORMAT" that is outside of the heap ["PTR_FORMAT", "PTR_FORMAT")", 50 p2i(addr), p2i(reserved_region().start()), p2i(reserved_region().end()))); 51 return (uint)(pointer_delta(addr, reserved_region().start(), sizeof(uint8_t)) >> HeapRegion::LogOfHRGrainBytes); 52 } 53 54 inline HeapWord* G1CollectedHeap::bottom_addr_for_region(uint index) const { 55 return _hrm.reserved().start() + index * HeapRegion::GrainWords; 56 } 57 58 template <class T> 59 inline HeapRegion* G1CollectedHeap::heap_region_containing_raw(const T addr) const { 60 assert(addr != NULL, "invariant"); 61 assert(is_in_g1_reserved((const void*) addr), 62 err_msg("Address "PTR_FORMAT" is outside of the heap ranging from ["PTR_FORMAT" to "PTR_FORMAT")", 63 p2i((void*)addr), p2i(g1_reserved().start()), p2i(g1_reserved().end()))); 64 return _hrm.addr_to_region((HeapWord*) addr); 65 } 66 67 template <class T> 68 inline HeapRegion* G1CollectedHeap::heap_region_containing(const T addr) const { 69 HeapRegion* hr = heap_region_containing_raw(addr); 70 if (hr->is_continues_humongous()) { 71 return hr->humongous_start_region(); 72 } 73 return hr; 74 } 75 76 inline void G1CollectedHeap::reset_gc_time_stamp() { 77 _gc_time_stamp = 0; 78 OrderAccess::fence(); 79 // Clear the cached CSet starting regions and time stamps. 80 // Their validity is dependent on the GC timestamp. 81 clear_cset_start_regions(); 82 } 83 84 inline void G1CollectedHeap::increment_gc_time_stamp() { 85 ++_gc_time_stamp; 86 OrderAccess::fence(); 87 } 88 89 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) { 90 _old_set.remove(hr); 91 } 92 93 inline bool G1CollectedHeap::obj_in_cs(oop obj) { 94 HeapRegion* r = _hrm.addr_to_region((HeapWord*) obj); 95 return r != NULL && r->in_collection_set(); 96 } 97 98 inline HeapWord* G1CollectedHeap::attempt_allocation(size_t word_size, 99 unsigned int* gc_count_before_ret, 100 int* gclocker_retry_count_ret) { 101 assert_heap_not_locked_and_not_at_safepoint(); 102 assert(!is_humongous(word_size), "attempt_allocation() should not " 103 "be called for humongous allocation requests"); 104 105 AllocationContext_t context = AllocationContext::current(); 106 HeapWord* result = _allocator->mutator_alloc_region(context)->attempt_allocation(word_size, 107 false /* bot_updates */); 108 if (result == NULL) { 109 result = attempt_allocation_slow(word_size, 110 context, 111 gc_count_before_ret, 112 gclocker_retry_count_ret); 113 } 114 assert_heap_not_locked(); 115 if (result != NULL) { 116 dirty_young_block(result, word_size); 117 } 118 return result; 119 } 120 121 inline HeapWord* G1CollectedHeap::survivor_attempt_allocation(size_t word_size, 122 AllocationContext_t context) { 123 assert(!is_humongous(word_size), 124 "we should not be seeing humongous-size allocations in this path"); 125 126 HeapWord* result = _allocator->survivor_gc_alloc_region(context)->attempt_allocation(word_size, 127 false /* bot_updates */); 128 if (result == NULL) { 129 MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag); 130 result = _allocator->survivor_gc_alloc_region(context)->attempt_allocation_locked(word_size, 131 false /* bot_updates */); 132 } 133 if (result != NULL) { 134 dirty_young_block(result, word_size); 135 } 136 return result; 137 } 138 139 inline HeapWord* G1CollectedHeap::old_attempt_allocation(size_t word_size, 140 AllocationContext_t context) { 141 assert(!is_humongous(word_size), 142 "we should not be seeing humongous-size allocations in this path"); 143 144 HeapWord* result = _allocator->old_gc_alloc_region(context)->attempt_allocation(word_size, 145 true /* bot_updates */); 146 if (result == NULL) { 147 MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag); 148 result = _allocator->old_gc_alloc_region(context)->attempt_allocation_locked(word_size, 149 true /* bot_updates */); 150 } 151 return result; 152 } 153 154 // It dirties the cards that cover the block so that so that the post 155 // write barrier never queues anything when updating objects on this 156 // block. It is assumed (and in fact we assert) that the block 157 // belongs to a young region. 158 inline void 159 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) { 160 assert_heap_not_locked(); 161 162 // Assign the containing region to containing_hr so that we don't 163 // have to keep calling heap_region_containing_raw() in the 164 // asserts below. 165 DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing_raw(start);) 166 assert(word_size > 0, "pre-condition"); 167 assert(containing_hr->is_in(start), "it should contain start"); 168 assert(containing_hr->is_young(), "it should be young"); 169 assert(!containing_hr->is_humongous(), "it should not be humongous"); 170 171 HeapWord* end = start + word_size; 172 assert(containing_hr->is_in(end - 1), "it should also contain end - 1"); 173 174 MemRegion mr(start, end); 175 g1_barrier_set()->g1_mark_as_young(mr); 176 } 177 178 inline RefToScanQueue* G1CollectedHeap::task_queue(int i) const { 179 return _task_queues->queue(i); 180 } 181 182 inline bool G1CollectedHeap::isMarkedPrev(oop obj) const { 183 return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj); 184 } 185 186 inline bool G1CollectedHeap::isMarkedNext(oop obj) const { 187 return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj); 188 } 189 190 // This is a fast test on whether a reference points into the 191 // collection set or not. Assume that the reference 192 // points into the heap. 193 inline bool G1CollectedHeap::is_in_cset(oop obj) { 194 bool ret = _in_cset_fast_test.is_in_cset((HeapWord*)obj); 195 // let's make sure the result is consistent with what the slower 196 // test returns 197 assert( ret || !obj_in_cs(obj), "sanity"); 198 assert(!ret || obj_in_cs(obj), "sanity"); 199 return ret; 200 } 201 202 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) { 203 return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj); 204 } 205 206 G1CollectedHeap::in_cset_state_t G1CollectedHeap::in_cset_state(const oop obj) { 207 return _in_cset_fast_test.at((HeapWord*)obj); 208 } 209 210 void G1CollectedHeap::register_humongous_region_with_in_cset_fast_test(uint index) { 211 _in_cset_fast_test.set_humongous(index); 212 } 213 214 #ifndef PRODUCT 215 // Support for G1EvacuationFailureALot 216 217 inline bool 218 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young, 219 bool during_initial_mark, 220 bool during_marking) { 221 bool res = false; 222 if (during_marking) { 223 res |= G1EvacuationFailureALotDuringConcMark; 224 } 225 if (during_initial_mark) { 226 res |= G1EvacuationFailureALotDuringInitialMark; 227 } 228 if (gcs_are_young) { 229 res |= G1EvacuationFailureALotDuringYoungGC; 230 } else { 231 // GCs are mixed 232 res |= G1EvacuationFailureALotDuringMixedGC; 233 } 234 return res; 235 } 236 237 inline void 238 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() { 239 if (G1EvacuationFailureALot) { 240 // Note we can't assert that _evacuation_failure_alot_for_current_gc 241 // is clear here. It may have been set during a previous GC but that GC 242 // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to 243 // trigger an evacuation failure and clear the flags and and counts. 244 245 // Check if we have gone over the interval. 246 const size_t gc_num = total_collections(); 247 const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number; 248 249 _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval); 250 251 // Now check if G1EvacuationFailureALot is enabled for the current GC type. 252 const bool gcs_are_young = g1_policy()->gcs_are_young(); 253 const bool during_im = g1_policy()->during_initial_mark_pause(); 254 const bool during_marking = mark_in_progress(); 255 256 _evacuation_failure_alot_for_current_gc &= 257 evacuation_failure_alot_for_gc_type(gcs_are_young, 258 during_im, 259 during_marking); 260 } 261 } 262 263 inline bool G1CollectedHeap::evacuation_should_fail() { 264 if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) { 265 return false; 266 } 267 // G1EvacuationFailureALot is in effect for current GC 268 // Access to _evacuation_failure_alot_count is not atomic; 269 // the value does not have to be exact. 270 if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) { 271 return false; 272 } 273 _evacuation_failure_alot_count = 0; 274 return true; 275 } 276 277 inline void G1CollectedHeap::reset_evacuation_should_fail() { 278 if (G1EvacuationFailureALot) { 279 _evacuation_failure_alot_gc_number = total_collections(); 280 _evacuation_failure_alot_count = 0; 281 _evacuation_failure_alot_for_current_gc = false; 282 } 283 } 284 #endif // #ifndef PRODUCT 285 286 inline bool G1CollectedHeap::is_in_young(const oop obj) { 287 if (obj == NULL) { 288 return false; 289 } 290 return heap_region_containing(obj)->is_young(); 291 } 292 293 // We don't need barriers for initializing stores to objects 294 // in the young gen: for the SATB pre-barrier, there is no 295 // pre-value that needs to be remembered; for the remembered-set 296 // update logging post-barrier, we don't maintain remembered set 297 // information for young gen objects. 298 inline bool G1CollectedHeap::can_elide_initializing_store_barrier(oop new_obj) { 299 return is_in_young(new_obj); 300 } 301 302 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const { 303 if (obj == NULL) { 304 return false; 305 } 306 return is_obj_dead(obj, heap_region_containing(obj)); 307 } 308 309 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const { 310 if (obj == NULL) { 311 return false; 312 } 313 return is_obj_ill(obj, heap_region_containing(obj)); 314 } 315 316 inline void G1CollectedHeap::set_humongous_is_live(oop obj) { 317 uint region = addr_to_region((HeapWord*)obj); 318 // We not only set the "live" flag in the humongous_is_live table, but also 319 // reset the entry in the _in_cset_fast_test table so that subsequent references 320 // to the same humongous object do not go into the slow path again. 321 // This is racy, as multiple threads may at the same time enter here, but this 322 // is benign. 323 // During collection we only ever set the "live" flag, and only ever clear the 324 // entry in the in_cset_fast_table. 325 // We only ever evaluate the contents of these tables (in the VM thread) after 326 // having synchronized the worker threads with the VM thread, or in the same 327 // thread (i.e. within the VM thread). 328 if (!_humongous_is_live.is_live(region)) { 329 _humongous_is_live.set_live(region); 330 _in_cset_fast_test.clear_humongous(region); 331 } 332 } 333 334 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP