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.
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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/heapRegionSet.inline.hpp"
34 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
35 #include "runtime/orderAccess.inline.hpp"
36 #include "utilities/taskqueue.hpp"
37
38 // Inline functions for G1CollectedHeap
39
40 // Return the region with the given index. It assumes the index is valid.
41 inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrs.at(index); }
42
43 inline uint G1CollectedHeap::addr_to_region(HeapWord* addr) const {
44 assert(is_in_reserved(addr),
45 err_msg("Cannot calculate region index for address "PTR_FORMAT" that is outside of the heap ["PTR_FORMAT", "PTR_FORMAT")",
46 p2i(addr), p2i(_reserved.start()), p2i(_reserved.end())));
47 return (uint)(pointer_delta(addr, _reserved.start(), sizeof(uint8_t)) >> HeapRegion::LogOfHRGrainBytes);
48 }
49
50 template <class T>
51 inline HeapRegion*
52 G1CollectedHeap::heap_region_containing_raw(const T addr) const {
53 assert(addr != NULL, "invariant");
54 assert(_g1_reserved.contains((const void*) addr),
55 err_msg("Address "PTR_FORMAT" is outside of the heap ranging from ["PTR_FORMAT" to "PTR_FORMAT")",
56 p2i((void*)addr), p2i(_g1_reserved.start()), p2i(_g1_reserved.end())));
57 return _hrs.addr_to_region((HeapWord*) addr);
58 }
59
60 template <class T>
61 inline HeapRegion*
62 G1CollectedHeap::heap_region_containing(const T addr) const {
63 HeapRegion* hr = heap_region_containing_raw(addr);
64 if (hr->continuesHumongous()) {
65 return hr->humongous_start_region();
66 }
67 return hr;
68 }
69
70 inline void G1CollectedHeap::reset_gc_time_stamp() {
71 _gc_time_stamp = 0;
72 OrderAccess::fence();
73 // Clear the cached CSet starting regions and time stamps.
74 // Their validity is dependent on the GC timestamp.
75 clear_cset_start_regions();
76 }
77
78 inline void G1CollectedHeap::increment_gc_time_stamp() {
79 ++_gc_time_stamp;
80 OrderAccess::fence();
81 }
82
83 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) {
84 _old_set.remove(hr);
85 }
86
87 inline bool G1CollectedHeap::obj_in_cs(oop obj) {
88 HeapRegion* r = _hrs.addr_to_region((HeapWord*) obj);
89 return r != NULL && r->in_collection_set();
90 }
91
92 inline HeapWord*
93 G1CollectedHeap::attempt_allocation(size_t word_size,
94 unsigned int* gc_count_before_ret,
95 int* gclocker_retry_count_ret) {
96 assert_heap_not_locked_and_not_at_safepoint();
97 assert(!isHumongous(word_size), "attempt_allocation() should not "
98 "be called for humongous allocation requests");
99
100 HeapWord* result = _mutator_alloc_region.attempt_allocation(word_size,
101 false /* bot_updates */);
102 if (result == NULL) {
103 result = attempt_allocation_slow(word_size,
104 gc_count_before_ret,
105 gclocker_retry_count_ret);
106 }
107 assert_heap_not_locked();
108 if (result != NULL) {
109 dirty_young_block(result, word_size);
110 }
111 return result;
112 }
113
114 inline HeapWord* G1CollectedHeap::survivor_attempt_allocation(size_t
115 word_size) {
116 assert(!isHumongous(word_size),
117 "we should not be seeing humongous-size allocations in this path");
118
119 HeapWord* result = _survivor_gc_alloc_region.attempt_allocation(word_size,
120 false /* bot_updates */);
121 if (result == NULL) {
122 MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
123 result = _survivor_gc_alloc_region.attempt_allocation_locked(word_size,
124 false /* bot_updates */);
125 }
126 if (result != NULL) {
127 dirty_young_block(result, word_size);
128 }
129 return result;
130 }
131
132 inline HeapWord* G1CollectedHeap::old_attempt_allocation(size_t word_size) {
133 assert(!isHumongous(word_size),
134 "we should not be seeing humongous-size allocations in this path");
135
136 HeapWord* result = _old_gc_alloc_region.attempt_allocation(word_size,
137 true /* bot_updates */);
138 if (result == NULL) {
139 MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
140 result = _old_gc_alloc_region.attempt_allocation_locked(word_size,
141 true /* bot_updates */);
142 }
143 return result;
144 }
145
146 // It dirties the cards that cover the block so that so that the post
147 // write barrier never queues anything when updating objects on this
148 // block. It is assumed (and in fact we assert) that the block
149 // belongs to a young region.
150 inline void
151 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
152 assert_heap_not_locked();
153
154 // Assign the containing region to containing_hr so that we don't
155 // have to keep calling heap_region_containing_raw() in the
156 // asserts below.
157 DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing_raw(start);)
158 assert(word_size > 0, "pre-condition");
159 assert(containing_hr->is_in(start), "it should contain start");
160 assert(containing_hr->is_young(), "it should be young");
161 assert(!containing_hr->isHumongous(), "it should not be humongous");
162
163 HeapWord* end = start + word_size;
164 assert(containing_hr->is_in(end - 1), "it should also contain end - 1");
165
166 MemRegion mr(start, end);
167 g1_barrier_set()->g1_mark_as_young(mr);
168 }
169
170 inline RefToScanQueue* G1CollectedHeap::task_queue(int i) const {
171 return _task_queues->queue(i);
172 }
173
174 inline bool G1CollectedHeap::isMarkedPrev(oop obj) const {
175 return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj);
176 }
177
178 inline bool G1CollectedHeap::isMarkedNext(oop obj) const {
179 return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj);
180 }
181
182 // This is a fast test on whether a reference points into the
183 // collection set or not. Assume that the reference
184 // points into the heap.
185 inline bool G1CollectedHeap::is_in_cset(oop obj) {
186 bool ret = _in_cset_fast_test.is_in_cset((HeapWord*)obj);
187 // let's make sure the result is consistent with what the slower
188 // test returns
189 assert( ret || !obj_in_cs(obj), "sanity");
190 assert(!ret || obj_in_cs(obj), "sanity");
191 return ret;
192 }
193
194 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) {
195 return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj);
196 }
197
198 G1CollectedHeap::in_cset_state_t G1CollectedHeap::in_cset_state(const oop obj) {
199 return _in_cset_fast_test.at((HeapWord*)obj);
200 }
201
202 void G1CollectedHeap::register_humongous_region_with_in_cset_fast_test(uint index) {
203 _in_cset_fast_test.set_humongous(index);
204 }
205
206 #ifndef PRODUCT
207 // Support for G1EvacuationFailureALot
208
209 inline bool
210 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young,
211 bool during_initial_mark,
212 bool during_marking) {
213 bool res = false;
214 if (during_marking) {
215 res |= G1EvacuationFailureALotDuringConcMark;
216 }
217 if (during_initial_mark) {
218 res |= G1EvacuationFailureALotDuringInitialMark;
219 }
220 if (gcs_are_young) {
221 res |= G1EvacuationFailureALotDuringYoungGC;
222 } else {
223 // GCs are mixed
224 res |= G1EvacuationFailureALotDuringMixedGC;
225 }
226 return res;
227 }
228
229 inline void
230 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() {
231 if (G1EvacuationFailureALot) {
232 // Note we can't assert that _evacuation_failure_alot_for_current_gc
233 // is clear here. It may have been set during a previous GC but that GC
234 // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to
235 // trigger an evacuation failure and clear the flags and and counts.
236
237 // Check if we have gone over the interval.
238 const size_t gc_num = total_collections();
239 const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number;
240
241 _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval);
242
243 // Now check if G1EvacuationFailureALot is enabled for the current GC type.
244 const bool gcs_are_young = g1_policy()->gcs_are_young();
245 const bool during_im = g1_policy()->during_initial_mark_pause();
246 const bool during_marking = mark_in_progress();
247
248 _evacuation_failure_alot_for_current_gc &=
249 evacuation_failure_alot_for_gc_type(gcs_are_young,
250 during_im,
251 during_marking);
252 }
253 }
254
255 inline bool
256 G1CollectedHeap::evacuation_should_fail() {
257 if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) {
258 return false;
259 }
260 // G1EvacuationFailureALot is in effect for current GC
261 // Access to _evacuation_failure_alot_count is not atomic;
262 // the value does not have to be exact.
263 if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) {
264 return false;
265 }
266 _evacuation_failure_alot_count = 0;
267 return true;
268 }
269
270 inline void G1CollectedHeap::reset_evacuation_should_fail() {
271 if (G1EvacuationFailureALot) {
272 _evacuation_failure_alot_gc_number = total_collections();
273 _evacuation_failure_alot_count = 0;
274 _evacuation_failure_alot_for_current_gc = false;
275 }
276 }
277 #endif // #ifndef PRODUCT
278
279 inline bool G1CollectedHeap::is_in_young(const oop obj) {
280 if (obj == NULL) {
281 return false;
282 }
283 return heap_region_containing(obj)->is_young();
284 }
285
286 // We don't need barriers for initializing stores to objects
287 // in the young gen: for the SATB pre-barrier, there is no
288 // pre-value that needs to be remembered; for the remembered-set
289 // update logging post-barrier, we don't maintain remembered set
290 // information for young gen objects.
291 inline bool G1CollectedHeap::can_elide_initializing_store_barrier(oop new_obj) {
292 return is_in_young(new_obj);
293 }
294
295 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const {
296 if (obj == NULL) {
297 return false;
298 }
299 return is_obj_dead(obj, heap_region_containing(obj));
300 }
301
302 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const {
303 if (obj == NULL) {
304 return false;
305 }
306 return is_obj_ill(obj, heap_region_containing(obj));
307 }
308
309 inline void G1CollectedHeap::set_humongous_is_live(oop obj) {
310 uint region = addr_to_region((HeapWord*)obj);
311 // We not only set the "live" flag in the humongous_is_live table, but also
312 // reset the entry in the _in_cset_fast_test table so that subsequent references
313 // to the same humongous object do not go into the slow path again.
314 // This is racy, as multiple threads may at the same time enter here, but this
315 // is benign.
316 // During collection we only ever set the "live" flag, and only ever clear the
317 // entry in the in_cset_fast_table.
318 // We only ever evaluate the contents of these tables (in the VM thread) after
319 // having synchronized the worker threads with the VM thread, or in the same
320 // thread (i.e. within the VM thread).
321 if (!_humongous_is_live.is_live(region)) {
322 _humongous_is_live.set_live(region);
323 _in_cset_fast_test.clear_humongous(region);
324 }
325 }
326
327 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP