1 /* 2 * Copyright (c) 2001, 2015, 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/concurrentMark.hpp" 29 #include "gc/g1/g1CollectedHeap.hpp" 30 #include "gc/g1/g1CollectorPolicy.hpp" 31 #include "gc/g1/g1CollectorState.hpp" 32 #include "gc/g1/g1SATBCardTableModRefBS.hpp" 33 #include "gc/g1/heapRegionManager.inline.hpp" 34 #include "gc/g1/heapRegionSet.inline.hpp" 35 #include "gc/shared/taskqueue.hpp" 36 #include "runtime/orderAccess.inline.hpp" 37 38 G1EvacStats* G1CollectedHeap::alloc_buffer_stats(InCSetState dest) { 39 switch (dest.value()) { 40 case InCSetState::Young: 41 return &_survivor_evac_stats; 42 case InCSetState::Old: 43 return &_old_evac_stats; 44 default: 45 ShouldNotReachHere(); 46 return NULL; // Keep some compilers happy 47 } 48 } 49 50 size_t G1CollectedHeap::desired_plab_sz(InCSetState dest) { 51 size_t gclab_word_size = alloc_buffer_stats(dest)->desired_plab_sz(G1CollectedHeap::heap()->workers()->active_workers()); 52 // Prevent humongous PLAB sizes for two reasons: 53 // * PLABs are allocated using a similar paths as oops, but should 54 // never be in a humongous region 55 // * Allowing humongous PLABs needlessly churns the region free lists 56 return MIN2(_humongous_object_threshold_in_words, gclab_word_size); 57 } 58 59 // Inline functions for G1CollectedHeap 60 61 inline AllocationContextStats& G1CollectedHeap::allocation_context_stats() { 62 return _allocation_context_stats; 63 } 64 65 // Return the region with the given index. It assumes the index is valid. 66 inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrm.at(index); } 67 68 inline HeapRegion* G1CollectedHeap::next_region_in_humongous(HeapRegion* hr) const { 69 return _hrm.next_region_in_humongous(hr); 70 } 71 72 inline uint G1CollectedHeap::addr_to_region(HeapWord* addr) const { 73 assert(is_in_reserved(addr), 74 "Cannot calculate region index for address " PTR_FORMAT " that is outside of the heap [" PTR_FORMAT ", " PTR_FORMAT ")", 75 p2i(addr), p2i(reserved_region().start()), p2i(reserved_region().end())); 76 return (uint)(pointer_delta(addr, reserved_region().start(), sizeof(uint8_t)) >> HeapRegion::LogOfHRGrainBytes); 77 } 78 79 inline HeapWord* G1CollectedHeap::bottom_addr_for_region(uint index) const { 80 return _hrm.reserved().start() + index * HeapRegion::GrainWords; 81 } 82 83 template <class T> 84 inline HeapRegion* G1CollectedHeap::heap_region_containing(const T addr) const { 85 assert(addr != NULL, "invariant"); 86 assert(is_in_g1_reserved((const void*) addr), 87 "Address " PTR_FORMAT " is outside of the heap ranging from [" PTR_FORMAT " to " PTR_FORMAT ")", 88 p2i((void*)addr), p2i(g1_reserved().start()), p2i(g1_reserved().end())); 89 return _hrm.addr_to_region((HeapWord*) addr); 90 } 91 92 inline void G1CollectedHeap::reset_gc_time_stamp() { 93 _gc_time_stamp = 0; 94 OrderAccess::fence(); 95 // Clear the cached CSet starting regions and time stamps. 96 // Their validity is dependent on the GC timestamp. 97 clear_cset_start_regions(); 98 } 99 100 inline void G1CollectedHeap::increment_gc_time_stamp() { 101 ++_gc_time_stamp; 102 OrderAccess::fence(); 103 } 104 105 inline void G1CollectedHeap::old_set_add(HeapRegion* hr) { 106 _old_set.add(hr); 107 } 108 109 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) { 110 _old_set.remove(hr); 111 } 112 113 // It dirties the cards that cover the block so that so that the post 114 // write barrier never queues anything when updating objects on this 115 // block. It is assumed (and in fact we assert) that the block 116 // belongs to a young region. 117 inline void 118 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) { 119 assert_heap_not_locked(); 120 121 // Assign the containing region to containing_hr so that we don't 122 // have to keep calling heap_region_containing() in the 123 // asserts below. 124 DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing(start);) 125 assert(word_size > 0, "pre-condition"); 126 assert(containing_hr->is_in(start), "it should contain start"); 127 assert(containing_hr->is_young(), "it should be young"); 128 assert(!containing_hr->is_humongous(), "it should not be humongous"); 129 130 HeapWord* end = start + word_size; 131 assert(containing_hr->is_in(end - 1), "it should also contain end - 1"); 132 133 MemRegion mr(start, end); 134 g1_barrier_set()->g1_mark_as_young(mr); 135 } 136 137 inline RefToScanQueue* G1CollectedHeap::task_queue(uint i) const { 138 return _task_queues->queue(i); 139 } 140 141 inline bool G1CollectedHeap::isMarkedPrev(oop obj) const { 142 return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj); 143 } 144 145 inline bool G1CollectedHeap::isMarkedNext(oop obj) const { 146 return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj); 147 } 148 149 // This is a fast test on whether a reference points into the 150 // collection set or not. Assume that the reference 151 // points into the heap. 152 inline bool G1CollectedHeap::is_in_cset(oop obj) { 153 bool ret = _in_cset_fast_test.is_in_cset((HeapWord*)obj); 154 // let's make sure the result is consistent with what the slower 155 // test returns 156 assert( ret || !obj_in_cs(obj), "sanity"); 157 assert(!ret || obj_in_cs(obj), "sanity"); 158 return ret; 159 } 160 161 bool G1CollectedHeap::is_in_cset(const HeapRegion* hr) { 162 return _in_cset_fast_test.is_in_cset(hr); 163 } 164 165 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) { 166 return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj); 167 } 168 169 InCSetState G1CollectedHeap::in_cset_state(const oop obj) { 170 return _in_cset_fast_test.at((HeapWord*)obj); 171 } 172 173 void G1CollectedHeap::register_humongous_region_with_cset(uint index) { 174 _in_cset_fast_test.set_humongous(index); 175 } 176 177 #ifndef PRODUCT 178 // Support for G1EvacuationFailureALot 179 180 inline bool 181 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young, 182 bool during_initial_mark, 183 bool during_marking) { 184 bool res = false; 185 if (during_marking) { 186 res |= G1EvacuationFailureALotDuringConcMark; 187 } 188 if (during_initial_mark) { 189 res |= G1EvacuationFailureALotDuringInitialMark; 190 } 191 if (gcs_are_young) { 192 res |= G1EvacuationFailureALotDuringYoungGC; 193 } else { 194 // GCs are mixed 195 res |= G1EvacuationFailureALotDuringMixedGC; 196 } 197 return res; 198 } 199 200 inline void 201 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() { 202 if (G1EvacuationFailureALot) { 203 // Note we can't assert that _evacuation_failure_alot_for_current_gc 204 // is clear here. It may have been set during a previous GC but that GC 205 // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to 206 // trigger an evacuation failure and clear the flags and and counts. 207 208 // Check if we have gone over the interval. 209 const size_t gc_num = total_collections(); 210 const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number; 211 212 _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval); 213 214 // Now check if G1EvacuationFailureALot is enabled for the current GC type. 215 const bool gcs_are_young = collector_state()->gcs_are_young(); 216 const bool during_im = collector_state()->during_initial_mark_pause(); 217 const bool during_marking = collector_state()->mark_in_progress(); 218 219 _evacuation_failure_alot_for_current_gc &= 220 evacuation_failure_alot_for_gc_type(gcs_are_young, 221 during_im, 222 during_marking); 223 } 224 } 225 226 inline bool G1CollectedHeap::evacuation_should_fail() { 227 if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) { 228 return false; 229 } 230 // G1EvacuationFailureALot is in effect for current GC 231 // Access to _evacuation_failure_alot_count is not atomic; 232 // the value does not have to be exact. 233 if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) { 234 return false; 235 } 236 _evacuation_failure_alot_count = 0; 237 return true; 238 } 239 240 inline void G1CollectedHeap::reset_evacuation_should_fail() { 241 if (G1EvacuationFailureALot) { 242 _evacuation_failure_alot_gc_number = total_collections(); 243 _evacuation_failure_alot_count = 0; 244 _evacuation_failure_alot_for_current_gc = false; 245 } 246 } 247 #endif // #ifndef PRODUCT 248 249 inline bool G1CollectedHeap::is_in_young(const oop obj) { 250 if (obj == NULL) { 251 return false; 252 } 253 return heap_region_containing(obj)->is_young(); 254 } 255 256 // We don't need barriers for initializing stores to objects 257 // in the young gen: for the SATB pre-barrier, there is no 258 // pre-value that needs to be remembered; for the remembered-set 259 // update logging post-barrier, we don't maintain remembered set 260 // information for young gen objects. 261 inline bool G1CollectedHeap::can_elide_initializing_store_barrier(oop new_obj) { 262 return is_in_young(new_obj); 263 } 264 265 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const { 266 if (obj == NULL) { 267 return false; 268 } 269 return is_obj_dead(obj, heap_region_containing(obj)); 270 } 271 272 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const { 273 if (obj == NULL) { 274 return false; 275 } 276 return is_obj_ill(obj, heap_region_containing(obj)); 277 } 278 279 inline void G1CollectedHeap::set_humongous_reclaim_candidate(uint region, bool value) { 280 assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object"); 281 _humongous_reclaim_candidates.set_candidate(region, value); 282 } 283 284 inline bool G1CollectedHeap::is_humongous_reclaim_candidate(uint region) { 285 assert(_hrm.at(region)->is_starts_humongous(), "Must start a humongous object"); 286 return _humongous_reclaim_candidates.is_candidate(region); 287 } 288 289 inline void G1CollectedHeap::set_humongous_is_live(oop obj) { 290 uint region = addr_to_region((HeapWord*)obj); 291 // Clear the flag in the humongous_reclaim_candidates table. Also 292 // reset the entry in the _in_cset_fast_test table so that subsequent references 293 // to the same humongous object do not go into the slow path again. 294 // This is racy, as multiple threads may at the same time enter here, but this 295 // is benign. 296 // During collection we only ever clear the "candidate" flag, and only ever clear the 297 // entry in the in_cset_fast_table. 298 // We only ever evaluate the contents of these tables (in the VM thread) after 299 // having synchronized the worker threads with the VM thread, or in the same 300 // thread (i.e. within the VM thread). 301 if (is_humongous_reclaim_candidate(region)) { 302 set_humongous_reclaim_candidate(region, false); 303 _in_cset_fast_test.clear_humongous(region); 304 } 305 } 306 307 #endif // SHARE_VM_GC_G1_G1COLLECTEDHEAP_INLINE_HPP