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/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 inline HeapWord* G1CollectedHeap::bottom_addr_for_region(uint index) const {
51 return _hrs.reserved().start() + index * HeapRegion::GrainWords;
52 }
53
54 template <class T>
55 inline HeapRegion* G1CollectedHeap::heap_region_containing_raw(const T addr) const {
56 assert(addr != NULL, "invariant");
57 assert(is_in_g1_reserved((const void*) addr),
58 err_msg("Address "PTR_FORMAT" is outside of the heap ranging from ["PTR_FORMAT" to "PTR_FORMAT")",
59 p2i((void*)addr), p2i(g1_reserved().start()), p2i(g1_reserved().end())));
60 return _hrs.addr_to_region((HeapWord*) addr);
61 }
62
63 template <class T>
64 inline HeapRegion* G1CollectedHeap::heap_region_containing(const T addr) const {
65 HeapRegion* hr = heap_region_containing_raw(addr);
66 if (hr->continuesHumongous()) {
67 return hr->humongous_start_region();
68 }
69 return hr;
70 }
71
72 inline void G1CollectedHeap::reset_gc_time_stamp() {
73 _gc_time_stamp = 0;
74 OrderAccess::fence();
75 // Clear the cached CSet starting regions and time stamps.
76 // Their validity is dependent on the GC timestamp.
77 clear_cset_start_regions();
78 }
79
80 inline void G1CollectedHeap::increment_gc_time_stamp() {
81 ++_gc_time_stamp;
82 OrderAccess::fence();
83 }
84
85 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) {
86 _old_set.remove(hr);
87 }
88
89 inline bool G1CollectedHeap::obj_in_cs(oop obj) {
90 HeapRegion* r = _hrs.addr_to_region((HeapWord*) obj);
91 return r != NULL && r->in_collection_set();
92 }
93
94 inline HeapWord* G1CollectedHeap::attempt_allocation(size_t word_size,
95 unsigned int* gc_count_before_ret,
96 int* gclocker_retry_count_ret) {
97 assert_heap_not_locked_and_not_at_safepoint();
98 assert(!isHumongous(word_size), "attempt_allocation() should not "
99 "be called for humongous allocation requests");
100
101 HeapWord* result = _mutator_alloc_region.attempt_allocation(word_size,
102 false /* bot_updates */);
103 if (result == NULL) {
104 result = attempt_allocation_slow(word_size,
105 gc_count_before_ret,
106 gclocker_retry_count_ret);
107 }
108 assert_heap_not_locked();
109 if (result != NULL) {
110 dirty_young_block(result, word_size);
111 }
112 return result;
113 }
114
115 inline HeapWord* G1CollectedHeap::survivor_attempt_allocation(size_t
116 word_size) {
117 assert(!isHumongous(word_size),
118 "we should not be seeing humongous-size allocations in this path");
119
120 HeapWord* result = _survivor_gc_alloc_region.attempt_allocation(word_size,
121 false /* bot_updates */);
122 if (result == NULL) {
123 MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
124 result = _survivor_gc_alloc_region.attempt_allocation_locked(word_size,
125 false /* bot_updates */);
126 }
127 if (result != NULL) {
128 dirty_young_block(result, word_size);
129 }
130 return result;
131 }
132
133 inline HeapWord* G1CollectedHeap::old_attempt_allocation(size_t word_size) {
134 assert(!isHumongous(word_size),
135 "we should not be seeing humongous-size allocations in this path");
136
137 HeapWord* result = _old_gc_alloc_region.attempt_allocation(word_size,
138 true /* bot_updates */);
139 if (result == NULL) {
140 MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
141 result = _old_gc_alloc_region.attempt_allocation_locked(word_size,
142 true /* bot_updates */);
143 }
144 return result;
145 }
146
147 // It dirties the cards that cover the block so that so that the post
148 // write barrier never queues anything when updating objects on this
149 // block. It is assumed (and in fact we assert) that the block
150 // belongs to a young region.
151 inline void
152 G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
153 assert_heap_not_locked();
154
155 // Assign the containing region to containing_hr so that we don't
156 // have to keep calling heap_region_containing_raw() in the
157 // asserts below.
158 DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing_raw(start);)
159 assert(word_size > 0, "pre-condition");
160 assert(containing_hr->is_in(start), "it should contain start");
161 assert(containing_hr->is_young(), "it should be young");
162 assert(!containing_hr->isHumongous(), "it should not be humongous");
163
164 HeapWord* end = start + word_size;
165 assert(containing_hr->is_in(end - 1), "it should also contain end - 1");
166
167 MemRegion mr(start, end);
168 g1_barrier_set()->g1_mark_as_young(mr);
169 }
170
171 inline RefToScanQueue* G1CollectedHeap::task_queue(int i) const {
172 return _task_queues->queue(i);
173 }
174
175 inline bool G1CollectedHeap::isMarkedPrev(oop obj) const {
176 return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj);
177 }
178
179 inline bool G1CollectedHeap::isMarkedNext(oop obj) const {
180 return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj);
181 }
182
183 // This is a fast test on whether a reference points into the
184 // collection set or not. Assume that the reference
185 // points into the heap.
186 inline bool G1CollectedHeap::is_in_cset(oop obj) {
187 bool ret = _in_cset_fast_test.is_in_cset((HeapWord*)obj);
188 // let's make sure the result is consistent with what the slower
189 // test returns
190 assert( ret || !obj_in_cs(obj), "sanity");
191 assert(!ret || obj_in_cs(obj), "sanity");
192 return ret;
193 }
194
195 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) {
196 return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj);
197 }
198
199 G1CollectedHeap::in_cset_state_t G1CollectedHeap::in_cset_state(const oop obj) {
200 return _in_cset_fast_test.at((HeapWord*)obj);
201 }
202
203 void G1CollectedHeap::register_humongous_region_with_in_cset_fast_test(uint index) {
204 _in_cset_fast_test.set_humongous(index);
205 }
206
207 #ifndef PRODUCT
208 // Support for G1EvacuationFailureALot
209
210 inline bool
211 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young,
212 bool during_initial_mark,
213 bool during_marking) {
214 bool res = false;
215 if (during_marking) {
216 res |= G1EvacuationFailureALotDuringConcMark;
217 }
218 if (during_initial_mark) {
219 res |= G1EvacuationFailureALotDuringInitialMark;
220 }
221 if (gcs_are_young) {
222 res |= G1EvacuationFailureALotDuringYoungGC;
223 } else {
224 // GCs are mixed
225 res |= G1EvacuationFailureALotDuringMixedGC;
226 }
227 return res;
228 }
229
230 inline void
231 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() {
232 if (G1EvacuationFailureALot) {
233 // Note we can't assert that _evacuation_failure_alot_for_current_gc
234 // is clear here. It may have been set during a previous GC but that GC
235 // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to
236 // trigger an evacuation failure and clear the flags and and counts.
237
238 // Check if we have gone over the interval.
239 const size_t gc_num = total_collections();
240 const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number;
241
242 _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval);
243
244 // Now check if G1EvacuationFailureALot is enabled for the current GC type.
245 const bool gcs_are_young = g1_policy()->gcs_are_young();
246 const bool during_im = g1_policy()->during_initial_mark_pause();
247 const bool during_marking = mark_in_progress();
248
249 _evacuation_failure_alot_for_current_gc &=
250 evacuation_failure_alot_for_gc_type(gcs_are_young,
251 during_im,
252 during_marking);
253 }
254 }
255
256 inline bool 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