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_G1OOPCLOSURES_INLINE_HPP
26 #define SHARE_VM_GC_G1_G1OOPCLOSURES_INLINE_HPP
27
28 #include "gc/g1/g1CollectedHeap.hpp"
29 #include "gc/g1/g1ConcurrentMark.inline.hpp"
30 #include "gc/g1/g1OopClosures.hpp"
31 #include "gc/g1/g1ParScanThreadState.inline.hpp"
32 #include "gc/g1/g1RemSet.hpp"
33 #include "gc/g1/g1RemSet.inline.hpp"
34 #include "gc/g1/heapRegion.inline.hpp"
35 #include "gc/g1/heapRegionRemSet.hpp"
36 #include "memory/iterator.inline.hpp"
37 #include "runtime/prefetch.inline.hpp"
38
39 /*
40 * This really ought to be an inline function, but apparently the C++
41 * compiler sometimes sees fit to ignore inline declarations. Sigh.
42 */
43
44 template <class T>
45 inline void FilterIntoCSClosure::do_oop_work(T* p) {
46 T heap_oop = oopDesc::load_heap_oop(p);
47 if (!oopDesc::is_null(heap_oop) &&
48 _g1->is_in_cset_or_humongous(oopDesc::decode_heap_oop_not_null(heap_oop))) {
49 _oc->do_oop(p);
50 }
51 }
52
53 template <class T>
54 inline void FilterOutOfRegionClosure::do_oop_nv(T* p) {
55 T heap_oop = oopDesc::load_heap_oop(p);
56 if (!oopDesc::is_null(heap_oop)) {
57 HeapWord* obj_hw = (HeapWord*)oopDesc::decode_heap_oop_not_null(heap_oop);
58 if (obj_hw < _r_bottom || obj_hw >= _r_end) {
59 _oc->do_oop(p);
60 }
61 }
62 }
63
64 // This closure is applied to the fields of the objects that have just been copied.
65 template <class T>
66 inline void G1ParScanClosure::do_oop_nv(T* p) {
67 T heap_oop = oopDesc::load_heap_oop(p);
68
69 if (!oopDesc::is_null(heap_oop)) {
70 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
71 const InCSetState state = _g1->in_cset_state(obj);
72 if (state.is_in_cset()) {
73 // We're not going to even bother checking whether the object is
74 // already forwarded or not, as this usually causes an immediate
75 // stall. We'll try to prefetch the object (for write, given that
76 // we might need to install the forwarding reference) and we'll
77 // get back to it when pop it from the queue
78 Prefetch::write(obj->mark_addr(), 0);
79 Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
80
81 // slightly paranoid test; I'm trying to catch potential
82 // problems before we go into push_on_queue to know where the
83 // problem is coming from
84 assert((obj == oopDesc::load_decode_heap_oop(p)) ||
85 (obj->is_forwarded() &&
86 obj->forwardee() == oopDesc::load_decode_heap_oop(p)),
87 "p should still be pointing to obj or to its forwardee");
88
89 _par_scan_state->push_on_queue(p);
90 } else {
91 if (state.is_humongous()) {
92 _g1->set_humongous_is_live(obj);
93 } else if (state.is_ext()) {
94 _par_scan_state->do_oop_ext(p);
95 }
96 _par_scan_state->update_rs(_from, p, obj);
97 }
98 }
99 }
100
101 template <class T>
102 inline void G1ParPushHeapRSClosure::do_oop_nv(T* p) {
103 T heap_oop = oopDesc::load_heap_oop(p);
104
105 if (!oopDesc::is_null(heap_oop)) {
106 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
107 const InCSetState state = _g1->in_cset_state(obj);
108 if (state.is_in_cset_or_humongous()) {
109 Prefetch::write(obj->mark_addr(), 0);
110 Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
111
112 // Place on the references queue
113 _par_scan_state->push_on_queue(p);
114 } else if (state.is_ext()) {
115 _par_scan_state->do_oop_ext(p);
116 } else {
117 assert(!_g1->obj_in_cs(obj), "checking");
118 }
119 }
120 }
121
122 template <class T>
123 inline void G1CMOopClosure::do_oop_nv(T* p) {
124 oop obj = oopDesc::load_decode_heap_oop(p);
125 _task->deal_with_reference(obj);
126 }
127
128 template <class T>
129 inline void G1RootRegionScanClosure::do_oop_nv(T* p) {
130 T heap_oop = oopDesc::load_heap_oop(p);
131 if (!oopDesc::is_null(heap_oop)) {
132 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
133 HeapRegion* hr = _g1h->heap_region_containing((HeapWord*) obj);
134 _cm->grayRoot(obj, obj->size(), _worker_id, hr);
135 }
136 }
137
138 template <class T>
139 inline void G1Mux2Closure::do_oop_work(T* p) {
140 // Apply first closure; then apply the second.
141 _c1->do_oop(p);
142 _c2->do_oop(p);
143 }
144 void G1Mux2Closure::do_oop(oop* p) { do_oop_work(p); }
145 void G1Mux2Closure::do_oop(narrowOop* p) { do_oop_work(p); }
146
147 template <class T>
148 inline void G1TriggerClosure::do_oop_work(T* p) {
149 // Record that this closure was actually applied (triggered).
150 _triggered = true;
151 }
152 void G1TriggerClosure::do_oop(oop* p) { do_oop_work(p); }
153 void G1TriggerClosure::do_oop(narrowOop* p) { do_oop_work(p); }
154
155 template <class T>
156 inline void G1InvokeIfNotTriggeredClosure::do_oop_work(T* p) {
157 if (!_trigger_cl->triggered()) {
158 _oop_cl->do_oop(p);
159 }
160 }
161 void G1InvokeIfNotTriggeredClosure::do_oop(oop* p) { do_oop_work(p); }
162 void G1InvokeIfNotTriggeredClosure::do_oop(narrowOop* p) { do_oop_work(p); }
163
164 template <class T>
165 inline void G1UpdateRSOrPushRefOopClosure::do_oop_work(T* p) {
166 oop obj = oopDesc::load_decode_heap_oop(p);
167 if (obj == NULL) {
168 return;
169 }
170
171 #ifdef ASSERT
172 // can't do because of races
173 // assert(obj == NULL || obj->is_oop(), "expected an oop");
174
175 // Do the safe subset of is_oop
176 #ifdef CHECK_UNHANDLED_OOPS
177 oopDesc* o = obj.obj();
178 #else
179 oopDesc* o = obj;
180 #endif // CHECK_UNHANDLED_OOPS
181 assert(((intptr_t)o & MinObjAlignmentInBytesMask) == 0, "not oop aligned");
182 assert(_g1->is_in_reserved(obj), "must be in heap");
183 #endif // ASSERT
184
185 assert(_from != NULL, "from region must be non-NULL");
186 assert(_from->is_in_reserved(p), "p is not in from");
187
188 HeapRegion* to = _g1->heap_region_containing(obj);
189 if (_from == to) {
190 // Normally this closure should only be called with cross-region references.
191 // But since Java threads are manipulating the references concurrently and we
192 // reload the values things may have changed.
193 return;
194 }
195
196 // The _record_refs_into_cset flag is true during the RSet
197 // updating part of an evacuation pause. It is false at all
198 // other times:
199 // * rebuilding the remembered sets after a full GC
200 // * during concurrent refinement.
201 // * updating the remembered sets of regions in the collection
202 // set in the event of an evacuation failure (when deferred
203 // updates are enabled).
204
205 if (_record_refs_into_cset && to->in_collection_set()) {
206 // We are recording references that point into the collection
207 // set and this particular reference does exactly that...
208 // If the referenced object has already been forwarded
209 // to itself, we are handling an evacuation failure and
210 // we have already visited/tried to copy this object
211 // there is no need to retry.
212 if (!self_forwarded(obj)) {
213 assert(_push_ref_cl != NULL, "should not be null");
214 // Push the reference in the refs queue of the G1ParScanThreadState
215 // instance for this worker thread.
216 _push_ref_cl->do_oop(p);
217 }
218
219 // Deferred updates to the CSet are either discarded (in the normal case),
220 // or processed (if an evacuation failure occurs) at the end
221 // of the collection.
222 // See G1RemSet::cleanup_after_oops_into_collection_set_do().
223 } else {
224 // We either don't care about pushing references that point into the
225 // collection set (i.e. we're not during an evacuation pause) _or_
226 // the reference doesn't point into the collection set. Either way
227 // we add the reference directly to the RSet of the region containing
228 // the referenced object.
229 assert(to->rem_set() != NULL, "Need per-region 'into' remsets.");
230 to->rem_set()->add_reference(p, _worker_i);
231 }
232 }
233 void G1UpdateRSOrPushRefOopClosure::do_oop(oop* p) { do_oop_work(p); }
234 void G1UpdateRSOrPushRefOopClosure::do_oop(narrowOop* p) { do_oop_work(p); }
235
236 template <class T>
237 void G1ParCopyHelper::do_klass_barrier(T* p, oop new_obj) {
238 if (_g1->heap_region_containing(new_obj)->is_young()) {
239 _scanned_klass->record_modified_oops();
240 }
241 }
242
243 void G1ParCopyHelper::mark_object(oop obj) {
244 assert(!_g1->heap_region_containing(obj)->in_collection_set(), "should not mark objects in the CSet");
245
246 // We know that the object is not moving so it's safe to read its size.
247 _cm->grayRoot(obj, (size_t) obj->size(), _worker_id);
248 }
249
250 void G1ParCopyHelper::mark_forwarded_object(oop from_obj, oop to_obj) {
251 assert(from_obj->is_forwarded(), "from obj should be forwarded");
252 assert(from_obj->forwardee() == to_obj, "to obj should be the forwardee");
253 assert(from_obj != to_obj, "should not be self-forwarded");
254
255 assert(_g1->heap_region_containing(from_obj)->in_collection_set(), "from obj should be in the CSet");
256 assert(!_g1->heap_region_containing(to_obj)->in_collection_set(), "should not mark objects in the CSet");
257
258 // The object might be in the process of being copied by another
259 // worker so we cannot trust that its to-space image is
260 // well-formed. So we have to read its size from its from-space
261 // image which we know should not be changing.
262 _cm->grayRoot(to_obj, (size_t) from_obj->size(), _worker_id);
263 }
264
265 template <G1Barrier barrier, G1Mark do_mark_object, bool use_ext>
266 template <class T>
267 void G1ParCopyClosure<barrier, do_mark_object, use_ext>::do_oop_work(T* p) {
268 T heap_oop = oopDesc::load_heap_oop(p);
269
270 if (oopDesc::is_null(heap_oop)) {
271 return;
272 }
273
274 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
275
276 assert(_worker_id == _par_scan_state->worker_id(), "sanity");
277
278 const InCSetState state = _g1->in_cset_state(obj);
279 if (state.is_in_cset()) {
280 oop forwardee;
281 markOop m = obj->mark();
282 if (m->is_marked()) {
283 forwardee = (oop) m->decode_pointer();
284 } else {
285 forwardee = _par_scan_state->copy_to_survivor_space(state, obj, m);
286 }
287 assert(forwardee != NULL, "forwardee should not be NULL");
288 oopDesc::encode_store_heap_oop(p, forwardee);
289 if (do_mark_object != G1MarkNone && forwardee != obj) {
290 // If the object is self-forwarded we don't need to explicitly
291 // mark it, the evacuation failure protocol will do so.
292 mark_forwarded_object(obj, forwardee);
293 }
294
295 if (barrier == G1BarrierKlass) {
296 do_klass_barrier(p, forwardee);
297 }
298 } else {
299 if (state.is_humongous()) {
300 _g1->set_humongous_is_live(obj);
301 }
302
303 if (use_ext && state.is_ext()) {
304 _par_scan_state->do_oop_ext(p);
305 }
306 // The object is not in collection set. If we're a root scanning
307 // closure during an initial mark pause then attempt to mark the object.
308 if (do_mark_object == G1MarkFromRoot) {
309 mark_object(obj);
310 }
311 }
312 }
313
314 #endif // SHARE_VM_GC_G1_G1OOPCLOSURES_INLINE_HPP