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_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
39template <class T>
40inline void G1ScanClosureBase::prefetch_and_push(T* p, const oop obj) {
41  // We're not going to even bother checking whether the object is
42  // already forwarded or not, as this usually causes an immediate
43  // stall. We'll try to prefetch the object (for write, given that
44  // we might need to install the forwarding reference) and we'll
45  // get back to it when pop it from the queue
46  Prefetch::write(obj->mark_addr(), 0);
47  Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
48
49  // slightly paranoid test; I'm trying to catch potential
50  // problems before we go into push_on_queue to know where the
51  // problem is coming from
52  assert((obj == oopDesc::load_decode_heap_oop(p)) ||
53         (obj->is_forwarded() &&
54         obj->forwardee() == oopDesc::load_decode_heap_oop(p)),
55         "p should still be pointing to obj or to its forwardee");
56
57  _par_scan_state->push_on_queue(p);
58}
59
60template <class T>
61inline void G1ScanClosureBase::handle_non_cset_obj_common(InCSetState const state, T* p, oop const obj) {
62  if (state.is_humongous()) {
63    _g1->set_humongous_is_live(obj);
64  } else if (state.is_ext()) {
65    _par_scan_state->do_oop_ext(p);
66  }
67}
68
69template <class T>
70inline void G1ScanEvacuatedObjClosure::do_oop_nv(T* p) {
71  T heap_oop = oopDesc::load_heap_oop(p);
72
73  if (oopDesc::is_null(heap_oop)) {
74    return;
75  }
76  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
77  const InCSetState state = _g1->in_cset_state(obj);
78  if (state.is_in_cset()) {
79    prefetch_and_push(p, obj);
80  } else {
81    if (HeapRegion::is_in_same_region(p, obj)) {
82      return;
83    }
84    handle_non_cset_obj_common(state, p, obj);
85    _par_scan_state->update_rs(_from, p, obj);
86  }
87}
88
89template <class T>
90inline void G1CMOopClosure::do_oop_nv(T* p) {
91  oop obj = oopDesc::load_decode_heap_oop(p);
92  _task->deal_with_reference(obj);
93}
94
95template <class T>
96inline void G1RootRegionScanClosure::do_oop_nv(T* p) {
97  T heap_oop = oopDesc::load_heap_oop(p);
98  if (oopDesc::is_null(heap_oop)) {
99    return;
100  }
101  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
102  _cm->mark_in_next_bitmap(obj);
103}
104
105template <class T>
106inline static void check_obj_during_refinement(T* p, oop const obj) {
107#ifdef ASSERT
108  G1CollectedHeap* g1 = G1CollectedHeap::heap();
109  // can't do because of races
110  // assert(oopDesc::is_oop_or_null(obj), "expected an oop");
111  assert(check_obj_alignment(obj), "not oop aligned");
112  assert(g1->is_in_reserved(obj), "must be in heap");
113
114  HeapRegion* from = g1->heap_region_containing(p);
115
116  assert(from != NULL, "from region must be non-NULL");
117  assert(from->is_in_reserved(p) ||
118         (from->is_humongous() &&
119          g1->heap_region_containing(p)->is_humongous() &&
120          from->humongous_start_region() == g1->heap_region_containing(p)->humongous_start_region()),
121         "p " PTR_FORMAT " is not in the same region %u or part of the correct humongous object starting at region %u.",
122         p2i(p), from->hrm_index(), from->humongous_start_region()->hrm_index());
123#endif // ASSERT
124}
125
126template <class T>
127inline void G1ConcurrentRefineOopClosure::do_oop_nv(T* p) {
128  T o = oopDesc::load_heap_oop(p);
129  if (oopDesc::is_null(o)) {
130    return;
131  }
132  oop obj = oopDesc::decode_heap_oop_not_null(o);
133
134  check_obj_during_refinement(p, obj);
135
136  if (HeapRegion::is_in_same_region(p, obj)) {
137    // Normally this closure should only be called with cross-region references.
138    // But since Java threads are manipulating the references concurrently and we
139    // reload the values things may have changed.
140    // Also this check lets slip through references from a humongous continues region
141    // to its humongous start region, as they are in different regions, and adds a
142    // remembered set entry. This is benign (apart from memory usage), as we never
143    // try to either evacuate or eager reclaim humonguous arrays of j.l.O.
144    return;
145  }
146
147  HeapRegion* to = _g1->heap_region_containing(obj);
148
149  assert(to->rem_set() != NULL, "Need per-region 'into' remsets.");
150  to->rem_set()->add_reference(p, _worker_i);
151}
152
153template <class T>
154inline void G1ScanObjsDuringUpdateRSClosure::do_oop_nv(T* p) {
155  T o = oopDesc::load_heap_oop(p);
156  if (oopDesc::is_null(o)) {
157    return;
158  }
159  oop obj = oopDesc::decode_heap_oop_not_null(o);
160
161  check_obj_during_refinement(p, obj);
162
163  assert(!_g1->is_in_cset((HeapWord*)p), "Oop originates from " PTR_FORMAT " (region: %u) which is in the collection set.", p2i(p), _g1->addr_to_region((HeapWord*)p));
164  const InCSetState state = _g1->in_cset_state(obj);
165  if (state.is_in_cset()) {
166    // Since the source is always from outside the collection set, here we implicitly know
167    // that this is a cross-region reference too.
168    prefetch_and_push(p, obj);
169  } else {
170    HeapRegion* to = _g1->heap_region_containing(obj);
171    if (_from == to) {
172      return;
173    }
174    handle_non_cset_obj_common(state, p, obj);
175    to->rem_set()->add_reference(p, _worker_i);
176  }
177}
178
179template <class T>
180inline void G1ScanObjsDuringScanRSClosure::do_oop_nv(T* p) {
181  T heap_oop = oopDesc::load_heap_oop(p);
182  if (oopDesc::is_null(heap_oop)) {
183    return;
184  }
185  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
186
187  const InCSetState state = _g1->in_cset_state(obj);
188  if (state.is_in_cset()) {
189    prefetch_and_push(p, obj);
190  } else {
191    if (HeapRegion::is_in_same_region(p, obj)) {
192      return;
193    }
194    handle_non_cset_obj_common(state, p, obj);
195  }
196}
197
198template <class T>
199void G1ParCopyHelper::do_klass_barrier(T* p, oop new_obj) {
200  if (_g1->heap_region_containing(new_obj)->is_young()) {
201    _scanned_klass->record_modified_oops();
202  }
203}
204
205void G1ParCopyHelper::mark_object(oop obj) {
206  assert(!_g1->heap_region_containing(obj)->in_collection_set(), "should not mark objects in the CSet");
207
208  _cm->mark_in_next_bitmap(obj);
209}
210
211void G1ParCopyHelper::mark_forwarded_object(oop from_obj, oop to_obj) {
212  assert(from_obj->is_forwarded(), "from obj should be forwarded");
213  assert(from_obj->forwardee() == to_obj, "to obj should be the forwardee");
214  assert(from_obj != to_obj, "should not be self-forwarded");
215
216  assert(_g1->heap_region_containing(from_obj)->in_collection_set(), "from obj should be in the CSet");
217  assert(!_g1->heap_region_containing(to_obj)->in_collection_set(), "should not mark objects in the CSet");
218
219  _cm->mark_in_next_bitmap(to_obj);
220}
221
222template <G1Barrier barrier, G1Mark do_mark_object, bool use_ext>
223template <class T>
224void G1ParCopyClosure<barrier, do_mark_object, use_ext>::do_oop_work(T* p) {
225  T heap_oop = oopDesc::load_heap_oop(p);
226
227  if (oopDesc::is_null(heap_oop)) {
228    return;
229  }
230
231  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
232
233  assert(_worker_id == _par_scan_state->worker_id(), "sanity");
234
235  const InCSetState state = _g1->in_cset_state(obj);
236  if (state.is_in_cset()) {
237    oop forwardee;
238    markOop m = obj->mark();
239    if (m->is_marked()) {
240      forwardee = (oop) m->decode_pointer();
241    } else {
242      forwardee = _par_scan_state->copy_to_survivor_space(state, obj, m);
243    }
244    assert(forwardee != NULL, "forwardee should not be NULL");
245    oopDesc::encode_store_heap_oop(p, forwardee);
246    if (do_mark_object != G1MarkNone && forwardee != obj) {
247      // If the object is self-forwarded we don't need to explicitly
248      // mark it, the evacuation failure protocol will do so.
249      mark_forwarded_object(obj, forwardee);
250    }
251
252    if (barrier == G1BarrierKlass) {
253      do_klass_barrier(p, forwardee);
254    }
255  } else {
256    if (state.is_humongous()) {
257      _g1->set_humongous_is_live(obj);
258    }
259
260    if (use_ext && state.is_ext()) {
261      _par_scan_state->do_oop_ext(p);
262    }
263    // The object is not in collection set. If we're a root scanning
264    // closure during an initial mark pause then attempt to mark the object.
265    if (do_mark_object == G1MarkFromRoot) {
266      mark_object(obj);
267    }
268  }
269}
270
271#endif // SHARE_VM_GC_G1_G1OOPCLOSURES_INLINE_HPP
272