1 /* 2 * Copyright (c) 2001, 2016, 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 _gc_time_stamp = 0; 93 OrderAccess::fence(); 94 // Clear the cached CSet starting regions and time stamps. 95 // Their validity is dependent on the GC timestamp. 96 clear_cset_start_regions(); 97 } 98 99 inline void G1CollectedHeap::increment_gc_time_stamp() { 100 ++_gc_time_stamp; 101 OrderAccess::fence(); 102 } 103 104 inline void G1CollectedHeap::old_set_add(HeapRegion* hr) { 105 _old_set.add(hr); 106 } 107 108 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) { 109 _old_set.remove(hr); 110 } 111 112 // It dirties the cards that cover the block so that the post 113 // write barrier never queues anything when updating objects on this 114 // block. It is assumed (and in fact we assert) that the block 115 // belongs to a young region. 116 inline void 117 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) { 118 assert_heap_not_locked(); 119 120 // Assign the containing region to containing_hr so that we don't 121 // have to keep calling heap_region_containing() in the 122 // asserts below. 123 DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing(start);) 124 assert(word_size > 0, "pre-condition"); 125 assert(containing_hr->is_in(start), "it should contain start"); 126 assert(containing_hr->is_young(), "it should be young"); 127 assert(!containing_hr->is_humongous(), "it should not be humongous"); 128 129 HeapWord* end = start + word_size; 130 assert(containing_hr->is_in(end - 1), "it should also contain end - 1"); 131 132 MemRegion mr(start, end); 133 g1_barrier_set()->g1_mark_as_young(mr); 134 } 135 136 inline RefToScanQueue* G1CollectedHeap::task_queue(uint i) const { 137 return _task_queues->queue(i); 138 } 139 140 inline bool G1CollectedHeap::isMarkedPrev(oop obj) const { 141 return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj); 142 } 143 144 inline bool G1CollectedHeap::isMarkedNext(oop obj) const { 145 return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj); 146 } 147 148 // This is a fast test on whether a reference points into the 149 // collection set or not. Assume that the reference 150 // points into the heap. 151 inline bool G1CollectedHeap::is_in_cset(oop obj) { 152 bool ret = _in_cset_fast_test.is_in_cset((HeapWord*)obj); 153 // let's make sure the result is consistent with what the slower 154 // test returns 155 assert( ret || !obj_in_cs(obj), "sanity"); 156 assert(!ret || obj_in_cs(obj), "sanity"); 157 return ret; 158 } 159 160 bool G1CollectedHeap::is_in_cset(const HeapRegion* hr) { 161 return _in_cset_fast_test.is_in_cset(hr); 162 } 163 164 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) { 165 return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj); 166 } 167 168 InCSetState G1CollectedHeap::in_cset_state(const oop obj) { 169 return _in_cset_fast_test.at((HeapWord*)obj); 170 } 171 172 void G1CollectedHeap::register_humongous_region_with_cset(uint index) { 173 _in_cset_fast_test.set_humongous(index); 174 } 175 176 #ifndef PRODUCT 177 // Support for G1EvacuationFailureALot 178 179 inline bool 180 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young, 181 bool during_initial_mark, 182 bool during_marking) { 183 bool res = false; 184 if (during_marking) { 185 res |= G1EvacuationFailureALotDuringConcMark; 186 } 187 if (during_initial_mark) { 188 res |= G1EvacuationFailureALotDuringInitialMark; 189 } 190 if (gcs_are_young) { 191 res |= G1EvacuationFailureALotDuringYoungGC; 192 } else { 193 // GCs are mixed 194 res |= G1EvacuationFailureALotDuringMixedGC; 195 } 196 return res; 197 } 198 199 inline void 200 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() { 201 if (G1EvacuationFailureALot) { 202 // Note we can't assert that _evacuation_failure_alot_for_current_gc 203 // is clear here. It may have been set during a previous GC but that GC 204 // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to 205 // trigger an evacuation failure and clear the flags and and counts. 206 207 // Check if we have gone over the interval. 208 const size_t gc_num = total_collections(); 209 const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number; 210 211 _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval); 212 213 // Now check if G1EvacuationFailureALot is enabled for the current GC type. 214 const bool gcs_are_young = collector_state()->gcs_are_young(); 215 const bool during_im = collector_state()->during_initial_mark_pause(); 216 const bool during_marking = collector_state()->mark_in_progress(); 217 218 _evacuation_failure_alot_for_current_gc &= 219 evacuation_failure_alot_for_gc_type(gcs_are_young, 220 during_im, 221 during_marking); 222 } 223 } 224 225 inline bool G1CollectedHeap::evacuation_should_fail() { 226 if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) { 227 return false; 228 } 229 // G1EvacuationFailureALot is in effect for current GC 230 // Access to _evacuation_failure_alot_count is not atomic; 231 // the value does not have to be exact. 232 if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) { 233 return false; 234 } 235 _evacuation_failure_alot_count = 0; 236 return true; 237 } 238 239 inline void G1CollectedHeap::reset_evacuation_should_fail() { 240 if (G1EvacuationFailureALot) { 241 _evacuation_failure_alot_gc_number = total_collections(); 242 _evacuation_failure_alot_count = 0; 243 _evacuation_failure_alot_for_current_gc = false; 244 } 245 } 246 #endif // #ifndef PRODUCT 247 248 inline bool G1CollectedHeap::is_in_young(const oop obj) { 249 if (obj == NULL) { 250 return false; 251 } 252 return heap_region_containing(obj)->is_young(); 253 } 254 255 // We don't need barriers for initializing stores to objects 256 // in the young gen: for the SATB pre-barrier, there is no 257 // pre-value that needs to be remembered; for the remembered-set 258 // update logging post-barrier, we don't maintain remembered set 259 // information for young gen objects. 260 inline bool G1CollectedHeap::can_elide_initializing_store_barrier(oop new_obj) { 261 return is_in_young(new_obj); 262 } 263 264 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const { 265 if (obj == NULL) { 266 return false; 267 } 268 return is_obj_dead(obj, heap_region_containing(obj)); 269 } 270 271 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const { 272 if (obj == NULL) { 273 return false; 274 } 275 return is_obj_ill(obj, heap_region_containing(obj)); 276 } 277 278 inline void G1CollectedHeap::set_humongous_reclaim_candidate(uint region, bool value) { 279 assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object"); 280 _humongous_reclaim_candidates.set_candidate(region, value); 281 } 282 283 inline bool G1CollectedHeap::is_humongous_reclaim_candidate(uint region) { 284 assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object"); 285 return _humongous_reclaim_candidates.is_candidate(region); 286 } 287 288 inline void G1CollectedHeap::set_humongous_is_live(oop obj) { 289 uint region = addr_to_region((HeapWord*)obj); 290 // Clear the flag in the humongous_reclaim_candidates table. Also 291 // reset the entry in the _in_cset_fast_test table so that subsequent references 292 // to the same humongous object do not go into the slow path again. 293 // This is racy, as multiple threads may at the same time enter here, but this 294 // is benign. 295 // During collection we only ever clear the "candidate" flag, and only ever clear the 296 // entry in the in_cset_fast_table. 297 // We only ever evaluate the contents of these tables (in the VM thread) after 298 // having synchronized the worker threads with the VM thread, or in the same 299 // thread (i.e. within the VM thread). 300 if (is_humongous_reclaim_candidate(region)) { 301 set_humongous_reclaim_candidate(region, false); 302 _in_cset_fast_test.clear_humongous(region); 303 } 304 } 305 306 #endif // SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP