1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24
25#ifndef SHARE_GC_G1_G1OOPCLOSURES_INLINE_HPP
26#define SHARE_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/heapRegion.inline.hpp"
34#include "gc/g1/heapRegionRemSet.hpp"
35#include "memory/iterator.inline.hpp"
36#include "oops/access.inline.hpp"
37#include "oops/compressedOops.inline.hpp"
38#include "oops/oopsHierarchy.hpp"
39#include "oops/oop.inline.hpp"
40#include "runtime/prefetch.inline.hpp"
41
42template <class T>
43inline void G1ScanClosureBase::prefetch_and_push(T* p, const oop obj) {
44 // We're not going to even bother checking whether the object is
45 // already forwarded or not, as this usually causes an immediate
46 // stall. We'll try to prefetch the object (for write, given that
47 // we might need to install the forwarding reference) and we'll
48 // get back to it when pop it from the queue
49 Prefetch::write(obj->mark_addr_raw(), 0);
50 Prefetch::read(obj->mark_addr_raw(), (HeapWordSize*2));
51
52 // slightly paranoid test; I'm trying to catch potential
53 // problems before we go into push_on_queue to know where the
54 // problem is coming from
55 assert((obj == RawAccess<>::oop_load(p)) ||
56 (obj->is_forwarded() &&
57 obj->forwardee() == RawAccess<>::oop_load(p)),
58 "p should still be pointing to obj or to its forwardee");
59
60 _par_scan_state->push_on_queue(p);
61}
62
63template <class T>
64inline void G1ScanClosureBase::handle_non_cset_obj_common(G1HeapRegionAttr const region_attr, T* p, oop const obj) {
65 if (region_attr.is_humongous()) {
66 _g1h->set_humongous_is_live(obj);
67 } else if (region_attr.is_optional()) {
68 _par_scan_state->remember_reference_into_optional_region(p);
69 }
70}
71
72inline void G1ScanClosureBase::trim_queue_partially() {
73 _par_scan_state->trim_queue_partially();
74}
75
76template <class T>
77inline void G1ScanEvacuatedObjClosure::do_oop_work(T* p) {
78 T heap_oop = RawAccess<>::oop_load(p);
79
80 if (CompressedOops::is_null(heap_oop)) {
81 return;
82 }
83 oop obj = CompressedOops::decode_not_null(heap_oop);
84 const G1HeapRegionAttr region_attr = _g1h->region_attr(obj);
85 if (region_attr.is_in_cset()) {
86 prefetch_and_push(p, obj);
87 } else if (!HeapRegion::is_in_same_region(p, obj)) {
88 handle_non_cset_obj_common(region_attr, p, obj);
89 assert(_scanning_in_young != Uninitialized, "Scan location has not been initialized.");
90 if (_scanning_in_young == True) {
91 return;
92 }
93 _par_scan_state->enqueue_card_if_tracked(region_attr, p, obj);
94 }
95}
96
97template <class T>
98inline void G1CMOopClosure::do_oop_work(T* p) {
99 _task->deal_with_reference(p);
100}
101
102template <class T>
103inline void G1RootRegionScanClosure::do_oop_work(T* p) {
104 T heap_oop = RawAccess<MO_VOLATILE>::oop_load(p);
105 if (CompressedOops::is_null(heap_oop)) {
106 return;
107 }
108 oop obj = CompressedOops::decode_not_null(heap_oop);
109 _cm->mark_in_next_bitmap(_worker_id, obj);
110}
111
112template <class T>
113inline static void check_obj_during_refinement(T* p, oop const obj) {
114#ifdef ASSERT
115 G1CollectedHeap* g1h = G1CollectedHeap::heap();
116 // can't do because of races
117 // assert(oopDesc::is_oop_or_null(obj), "expected an oop");
118 assert(check_obj_alignment(obj), "not oop aligned");
119 assert(g1h->is_in_reserved(obj), "must be in heap");
120
121 HeapRegion* from = g1h->heap_region_containing(p);
122
123 assert(from != NULL, "from region must be non-NULL");
124 assert(from->is_in_reserved(p) ||
125 (from->is_humongous() &&
126 g1h->heap_region_containing(p)->is_humongous() &&
127 from->humongous_start_region() == g1h->heap_region_containing(p)->humongous_start_region()),
128 "p " PTR_FORMAT " is not in the same region %u or part of the correct humongous object starting at region %u.",
129 p2i(p), from->hrm_index(), from->humongous_start_region()->hrm_index());
130#endif // ASSERT
131}
132
133template <class T>
134inline void G1ConcurrentRefineOopClosure::do_oop_work(T* p) {
135 T o = RawAccess<MO_VOLATILE>::oop_load(p);
136 if (CompressedOops::is_null(o)) {
137 return;
138 }
139 oop obj = CompressedOops::decode_not_null(o);
140
141 check_obj_during_refinement(p, obj);
142
143 if (HeapRegion::is_in_same_region(p, obj)) {
144 // Normally this closure should only be called with cross-region references.
145 // But since Java threads are manipulating the references concurrently and we
146 // reload the values things may have changed.
147 // Also this check lets slip through references from a humongous continues region
148 // to its humongous start region, as they are in different regions, and adds a
149 // remembered set entry. This is benign (apart from memory usage), as we never
150 // try to either evacuate or eager reclaim humonguous arrays of j.l.O.
151 return;
152 }
153
154 HeapRegionRemSet* to_rem_set = _g1h->heap_region_containing(obj)->rem_set();
155
156 assert(to_rem_set != NULL, "Need per-region 'into' remsets.");
157 if (to_rem_set->is_tracked()) {
158 to_rem_set->add_reference(p, _worker_i);
159 }
160}
161
162template <class T>
163inline void G1ScanCardClosure::do_oop_work(T* p) {
164 T o = RawAccess<>::oop_load(p);
165 if (CompressedOops::is_null(o)) {
166 return;
167 }
168 oop obj = CompressedOops::decode_not_null(o);
169
170 check_obj_during_refinement(p, obj);
171
172 assert(!_g1h->is_in_cset((HeapWord*)p),
173 "Oop originates from " PTR_FORMAT " (region: %u) which is in the collection set.",
174 p2i(p), _g1h->addr_to_region((HeapWord*)p));
175
176 const G1HeapRegionAttr region_attr = _g1h->region_attr(obj);
177 if (region_attr.is_in_cset()) {
178 // Since the source is always from outside the collection set, here we implicitly know
179 // that this is a cross-region reference too.
180 prefetch_and_push(p, obj);
181 } else if (!HeapRegion::is_in_same_region(p, obj)) {
182 handle_non_cset_obj_common(region_attr, p, obj);
183 _par_scan_state->enqueue_card_if_tracked(region_attr, p, obj);
184 }
185}
186
187template <class T>
188inline void G1ScanRSForOptionalClosure::do_oop_work(T* p) {
189 const G1HeapRegionAttr region_attr = _g1h->region_attr(p);
190 // Entries in the optional collection set may start to originate from the collection
191 // set after one or more increments. In this case, previously optional regions
192 // became actual collection set regions. Filter them out here.
193 if (region_attr.is_in_cset()) {
194 return;
195 }
196 _scan_cl->do_oop_work(p);
197 _scan_cl->trim_queue_partially();
198}
199
200void G1ParCopyHelper::do_cld_barrier(oop new_obj) {
201 if (_g1h->heap_region_containing(new_obj)->is_young()) {
202 _scanned_cld->record_modified_oops();
203 }
204}
205
206void G1ParCopyHelper::mark_object(oop obj) {
207 assert(!_g1h->heap_region_containing(obj)->in_collection_set(), "should not mark objects in the CSet");
208
209 // We know that the object is not moving so it's safe to read its size.
210 _cm->mark_in_next_bitmap(_worker_id, obj);
211}
212
213void G1ParCopyHelper::trim_queue_partially() {
214 _par_scan_state->trim_queue_partially();
215}
216
217template <G1Barrier barrier, G1Mark do_mark_object>
218template <class T>
219void G1ParCopyClosure<barrier, do_mark_object>::do_oop_work(T* p) {
220 T heap_oop = RawAccess<>::oop_load(p);
221
222 if (CompressedOops::is_null(heap_oop)) {
223 return;
224 }
225
226 oop obj = CompressedOops::decode_not_null(heap_oop);
227
228 assert(_worker_id == _par_scan_state->worker_id(), "sanity");
229
230 const G1HeapRegionAttr state = _g1h->region_attr(obj);
231 if (state.is_in_cset()) {
232 oop forwardee;
233 markOop m = obj->mark_raw();
234 if (m->is_marked()) {
235 forwardee = (oop) m->decode_pointer();
236 } else {
237 forwardee = _par_scan_state->copy_to_survivor_space(state, obj, m);
238 }
239 assert(forwardee != NULL, "forwardee should not be NULL");
240 RawAccess<IS_NOT_NULL>::oop_store(p, forwardee);
241
242 if (barrier == G1BarrierCLD) {
243 do_cld_barrier(forwardee);
244 }
245 } else {
246 if (state.is_humongous()) {
247 _g1h->set_humongous_is_live(obj);
248 } else if (state.is_optional()) {
249 _par_scan_state->remember_root_into_optional_region(p);
250 }
251
252 // The object is not in collection set. If we're a root scanning
253 // closure during an initial mark pause then attempt to mark the object.
254 if (do_mark_object == G1MarkFromRoot) {
255 mark_object(obj);
256 }
257 }
258 trim_queue_partially();
259}
260
261template <class T> void G1RebuildRemSetClosure::do_oop_work(T* p) {
262 oop const obj = RawAccess<MO_VOLATILE>::oop_load(p);
263 if (obj == NULL) {
264 return;
265 }
266
267 if (HeapRegion::is_in_same_region(p, obj)) {
268 return;
269 }
270
271 HeapRegion* to = _g1h->heap_region_containing(obj);
272 HeapRegionRemSet* rem_set = to->rem_set();
273 rem_set->add_reference(p, _worker_id);
274}
275
276#endif // SHARE_GC_G1_G1OOPCLOSURES_INLINE_HPP
277