1 /* 2 * Copyright (c) 2001, 2017, 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_G1_G1COLLECTEDHEAP_INLINE_HPP 26 #define SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP 27 28 #include "gc/g1/g1CollectedHeap.hpp" 29 #include "gc/g1/g1CollectorState.hpp" 30 #include "gc/g1/g1ConcurrentMark.inline.hpp" 31 #include "gc/g1/g1SATBCardTableModRefBS.hpp" 32 #include "gc/g1/heapRegionManager.inline.hpp" 33 #include "gc/g1/heapRegionSet.inline.hpp" 34 #include "gc/shared/taskqueue.hpp" 35 #include "runtime/orderAccess.inline.hpp" 36 37 G1EvacStats* G1CollectedHeap::alloc_buffer_stats(InCSetState dest) { 38 switch (dest.value()) { 39 case InCSetState::Young: 40 return &_survivor_evac_stats; 41 case InCSetState::Old: 42 return &_old_evac_stats; 43 default: 44 ShouldNotReachHere(); 45 return NULL; // Keep some compilers happy 46 } 47 } 48 49 size_t G1CollectedHeap::desired_plab_sz(InCSetState dest) { 50 size_t gclab_word_size = alloc_buffer_stats(dest)->desired_plab_sz(G1CollectedHeap::heap()->workers()->active_workers()); 51 // Prevent humongous PLAB sizes for two reasons: 52 // * PLABs are allocated using a similar paths as oops, but should 53 // never be in a humongous region 54 // * Allowing humongous PLABs needlessly churns the region free lists 55 return MIN2(_humongous_object_threshold_in_words, gclab_word_size); 56 } 57 58 // Inline functions for G1CollectedHeap 59 60 inline AllocationContextStats& G1CollectedHeap::allocation_context_stats() { 61 return _allocation_context_stats; 62 } 63 64 // Return the region with the given index. It assumes the index is valid. 65 inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrm.at(index); } 66 67 inline HeapRegion* G1CollectedHeap::next_region_in_humongous(HeapRegion* hr) const { 68 return _hrm.next_region_in_humongous(hr); 69 } 70 71 inline uint G1CollectedHeap::addr_to_region(HeapWord* addr) const { 72 assert(is_in_reserved(addr), 73 "Cannot calculate region index for address " PTR_FORMAT " that is outside of the heap [" PTR_FORMAT ", " PTR_FORMAT ")", 74 p2i(addr), p2i(reserved_region().start()), p2i(reserved_region().end())); 75 return (uint)(pointer_delta(addr, reserved_region().start(), sizeof(uint8_t)) >> HeapRegion::LogOfHRGrainBytes); 76 } 77 78 inline HeapWord* G1CollectedHeap::bottom_addr_for_region(uint index) const { 79 return _hrm.reserved().start() + index * HeapRegion::GrainWords; 80 } 81 82 template <class T> 83 inline HeapRegion* G1CollectedHeap::heap_region_containing(const T addr) const { 84 assert(addr != NULL, "invariant"); 85 assert(is_in_g1_reserved((const void*) addr), 86 "Address " PTR_FORMAT " is outside of the heap ranging from [" PTR_FORMAT " to " PTR_FORMAT ")", 87 p2i((void*)addr), p2i(g1_reserved().start()), p2i(g1_reserved().end())); 88 return _hrm.addr_to_region((HeapWord*) addr); 89 } 90 91 inline void G1CollectedHeap::reset_gc_time_stamp() { 92 assert_at_safepoint(true); 93 _gc_time_stamp = 0; 94 } 95 96 inline void G1CollectedHeap::increment_gc_time_stamp() { 97 assert_at_safepoint(true); 98 ++_gc_time_stamp; 99 } 100 101 inline void G1CollectedHeap::old_set_add(HeapRegion* hr) { 102 _old_set.add(hr); 103 } 104 105 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) { 106 _old_set.remove(hr); 107 } 108 109 // It dirties the cards that cover the block so that the post 110 // write barrier never queues anything when updating objects on this 111 // block. It is assumed (and in fact we assert) that the block 112 // belongs to a young region. 113 inline void 114 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) { 115 assert_heap_not_locked(); 116 117 // Assign the containing region to containing_hr so that we don't 118 // have to keep calling heap_region_containing() in the 119 // asserts below. 120 DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing(start);) 121 assert(word_size > 0, "pre-condition"); 122 assert(containing_hr->is_in(start), "it should contain start"); 123 assert(containing_hr->is_young(), "it should be young"); 124 assert(!containing_hr->is_humongous(), "it should not be humongous"); 125 126 HeapWord* end = start + word_size; 127 assert(containing_hr->is_in(end - 1), "it should also contain end - 1"); 128 129 MemRegion mr(start, end); 130 g1_barrier_set()->g1_mark_as_young(mr); 131 } 132 133 inline RefToScanQueue* G1CollectedHeap::task_queue(uint i) const { 134 return _task_queues->queue(i); 135 } 136 137 inline bool G1CollectedHeap::isMarkedNext(oop obj) const { 138 return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj); 139 } 140 141 inline bool G1CollectedHeap::is_in_cset(oop obj) { 142 return _in_cset_fast_test.is_in_cset((HeapWord*)obj); 143 } 144 145 bool G1CollectedHeap::is_in_cset(const HeapRegion* hr) { 146 return _in_cset_fast_test.is_in_cset(hr); 147 } 148 149 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) { 150 return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj); 151 } 152 153 InCSetState G1CollectedHeap::in_cset_state(const oop obj) { 154 return _in_cset_fast_test.at((HeapWord*)obj); 155 } 156 157 void G1CollectedHeap::register_humongous_region_with_cset(uint index) { 158 _in_cset_fast_test.set_humongous(index); 159 } 160 161 #ifndef PRODUCT 162 // Support for G1EvacuationFailureALot 163 164 inline bool 165 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young, 166 bool during_initial_mark, 167 bool during_marking) { 168 bool res = false; 169 if (during_marking) { 170 res |= G1EvacuationFailureALotDuringConcMark; 171 } 172 if (during_initial_mark) { 173 res |= G1EvacuationFailureALotDuringInitialMark; 174 } 175 if (gcs_are_young) { 176 res |= G1EvacuationFailureALotDuringYoungGC; 177 } else { 178 // GCs are mixed 179 res |= G1EvacuationFailureALotDuringMixedGC; 180 } 181 return res; 182 } 183 184 inline void 185 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() { 186 if (G1EvacuationFailureALot) { 187 // Note we can't assert that _evacuation_failure_alot_for_current_gc 188 // is clear here. It may have been set during a previous GC but that GC 189 // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to 190 // trigger an evacuation failure and clear the flags and and counts. 191 192 // Check if we have gone over the interval. 193 const size_t gc_num = total_collections(); 194 const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number; 195 196 _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval); 197 198 // Now check if G1EvacuationFailureALot is enabled for the current GC type. 199 const bool gcs_are_young = collector_state()->gcs_are_young(); 200 const bool during_im = collector_state()->during_initial_mark_pause(); 201 const bool during_marking = collector_state()->mark_in_progress(); 202 203 _evacuation_failure_alot_for_current_gc &= 204 evacuation_failure_alot_for_gc_type(gcs_are_young, 205 during_im, 206 during_marking); 207 } 208 } 209 210 inline bool G1CollectedHeap::evacuation_should_fail() { 211 if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) { 212 return false; 213 } 214 // G1EvacuationFailureALot is in effect for current GC 215 // Access to _evacuation_failure_alot_count is not atomic; 216 // the value does not have to be exact. 217 if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) { 218 return false; 219 } 220 _evacuation_failure_alot_count = 0; 221 return true; 222 } 223 224 inline void G1CollectedHeap::reset_evacuation_should_fail() { 225 if (G1EvacuationFailureALot) { 226 _evacuation_failure_alot_gc_number = total_collections(); 227 _evacuation_failure_alot_count = 0; 228 _evacuation_failure_alot_for_current_gc = false; 229 } 230 } 231 #endif // #ifndef PRODUCT 232 233 inline bool G1CollectedHeap::is_in_young(const oop obj) { 234 if (obj == NULL) { 235 return false; 236 } 237 return heap_region_containing(obj)->is_young(); 238 } 239 240 // We don't need barriers for initializing stores to objects 241 // in the young gen: for the SATB pre-barrier, there is no 242 // pre-value that needs to be remembered; for the remembered-set 243 // update logging post-barrier, we don't maintain remembered set 244 // information for young gen objects. 245 inline bool G1CollectedHeap::can_elide_initializing_store_barrier(oop new_obj) { 246 return is_in_young(new_obj); 247 } 248 249 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const { 250 if (obj == NULL) { 251 return false; 252 } 253 return is_obj_dead(obj, heap_region_containing(obj)); 254 } 255 256 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const { 257 if (obj == NULL) { 258 return false; 259 } 260 return is_obj_ill(obj, heap_region_containing(obj)); 261 } 262 263 inline void G1CollectedHeap::set_humongous_reclaim_candidate(uint region, bool value) { 264 assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object"); 265 _humongous_reclaim_candidates.set_candidate(region, value); 266 } 267 268 inline bool G1CollectedHeap::is_humongous_reclaim_candidate(uint region) { 269 assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object"); 270 return _humongous_reclaim_candidates.is_candidate(region); 271 } 272 273 inline void G1CollectedHeap::set_humongous_is_live(oop obj) { 274 uint region = addr_to_region((HeapWord*)obj); 275 // Clear the flag in the humongous_reclaim_candidates table. Also 276 // reset the entry in the _in_cset_fast_test table so that subsequent references 277 // to the same humongous object do not go into the slow path again. 278 // This is racy, as multiple threads may at the same time enter here, but this 279 // is benign. 280 // During collection we only ever clear the "candidate" flag, and only ever clear the 281 // entry in the in_cset_fast_table. 282 // We only ever evaluate the contents of these tables (in the VM thread) after 283 // having synchronized the worker threads with the VM thread, or in the same 284 // thread (i.e. within the VM thread). 285 if (is_humongous_reclaim_candidate(region)) { 286 set_humongous_reclaim_candidate(region, false); 287 _in_cset_fast_test.clear_humongous(region); 288 } 289 } 290 291 #endif // SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP