1 /*
2 * Copyright (c) 2015, 2018, Red Hat, Inc. and/or its affiliates.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAP_INLINE_HPP
25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAP_INLINE_HPP
26
27 #include "classfile/javaClasses.inline.hpp"
28 #include "gc/shared/markBitMap.inline.hpp"
29 #include "gc/shared/threadLocalAllocBuffer.inline.hpp"
30 #include "gc/shared/suspendibleThreadSet.hpp"
31 #include "gc/shenandoah/brooksPointer.inline.hpp"
32 #include "gc/shenandoah/shenandoahAsserts.hpp"
33 #include "gc/shenandoah/shenandoahBarrierSet.inline.hpp"
34 #include "gc/shenandoah/shenandoahCollectionSet.hpp"
35 #include "gc/shenandoah/shenandoahCollectionSet.inline.hpp"
36 #include "gc/shenandoah/shenandoahConcurrentThread.hpp"
37 #include "gc/shenandoah/shenandoahConnectionMatrix.inline.hpp"
38 #include "gc/shenandoah/shenandoahHeap.hpp"
39 #include "gc/shenandoah/shenandoahHeapRegionSet.hpp"
40 #include "gc/shenandoah/shenandoahHeapRegion.inline.hpp"
41 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
42 #include "gc/shenandoah/shenandoahUtils.hpp"
43 #include "oops/oop.inline.hpp"
44 #include "runtime/atomic.hpp"
45 #include "runtime/interfaceSupport.inline.hpp"
46 #include "runtime/prefetch.hpp"
47 #include "runtime/prefetch.inline.hpp"
48 #include "runtime/thread.hpp"
49 #include "utilities/copy.hpp"
50
51 template <class T>
52 void ShenandoahUpdateRefsClosure::do_oop_work(T* p) {
53 T o = RawAccess<>::oop_load(p);
54 if (!CompressedOops::is_null(o)) {
55 oop obj = CompressedOops::decode_not_null(o);
56 _heap->update_with_forwarded_not_null(p, obj);
57 }
58 }
59
60 void ShenandoahUpdateRefsClosure::do_oop(oop* p) { do_oop_work(p); }
61 void ShenandoahUpdateRefsClosure::do_oop(narrowOop* p) { do_oop_work(p); }
62
63 inline ShenandoahHeapRegion* ShenandoahRegionIterator::next() {
64 size_t new_index = Atomic::add((volatile size_t) 1, &_index);
65 // get_region() provides the bounds-check and returns NULL on OOB.
66 return _heap->get_region(new_index - 1);
67 }
68
69 /*
70 * Marks the object. Returns true if the object has not been marked before and has
71 * been marked by this thread. Returns false if the object has already been marked,
72 * or if a competing thread succeeded in marking this object.
73 */
74 inline bool ShenandoahHeap::mark_next(oop obj) const {
75 shenandoah_assert_not_forwarded(NULL, obj);
76 HeapWord* addr = (HeapWord*) obj;
77 return (! allocated_after_next_mark_start(addr)) && _next_mark_bit_map->parMark(addr);
78 }
79
80 inline bool ShenandoahHeap::is_marked_next(oop obj) const {
81 HeapWord* addr = (HeapWord*) obj;
82 return allocated_after_next_mark_start(addr) || _next_mark_bit_map->isMarked(addr);
83 }
84
85 inline bool ShenandoahHeap::is_marked_complete(oop obj) const {
86 HeapWord* addr = (HeapWord*) obj;
87 return allocated_after_complete_mark_start(addr) || _complete_mark_bit_map->isMarked(addr);
88 }
89
90 inline bool ShenandoahHeap::has_forwarded_objects() const {
91 return _gc_state.is_set(HAS_FORWARDED);
92 }
93
94 inline size_t ShenandoahHeap::heap_region_index_containing(const void* addr) const {
95 uintptr_t region_start = ((uintptr_t) addr);
96 uintptr_t index = (region_start - (uintptr_t) base()) >> ShenandoahHeapRegion::region_size_bytes_shift();
97 assert(index < num_regions(), "Region index is in bounds: " PTR_FORMAT, p2i(addr));
98 return index;
99 }
100
101 inline ShenandoahHeapRegion* const ShenandoahHeap::heap_region_containing(const void* addr) const {
102 size_t index = heap_region_index_containing(addr);
103 ShenandoahHeapRegion* const result = get_region(index);
104 assert(addr >= result->bottom() && addr < result->end(), "Heap region contains the address: " PTR_FORMAT, p2i(addr));
105 return result;
106 }
107
108 template <class T>
109 inline oop ShenandoahHeap::update_with_forwarded_not_null(T* p, oop obj) {
110 if (in_collection_set(obj)) {
111 shenandoah_assert_forwarded_except(p, obj, is_full_gc_in_progress() || cancelled_concgc());
112 obj = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
113 RawAccess<OOP_NOT_NULL>::oop_store(p, obj);
114 }
115 #ifdef ASSERT
116 else {
117 shenandoah_assert_not_forwarded(p, obj);
118 }
119 #endif
120 return obj;
121 }
122
123 template <class T>
124 inline oop ShenandoahHeap::maybe_update_with_forwarded(T* p) {
125 T o = RawAccess<>::oop_load(p);
126 if (!CompressedOops::is_null(o)) {
127 oop obj = CompressedOops::decode_not_null(o);
128 return maybe_update_with_forwarded_not_null(p, obj);
129 } else {
130 return NULL;
131 }
132 }
133
134 template <class T>
135 inline oop ShenandoahHeap::evac_update_with_forwarded(T* p, bool &evac) {
136 evac = false;
137 T o = RawAccess<>::oop_load(p);
138 if (!CompressedOops::is_null(o)) {
139 oop heap_oop = CompressedOops::decode_not_null(o);
140 if (in_collection_set(heap_oop)) {
141 oop forwarded_oop = ShenandoahBarrierSet::resolve_forwarded_not_null(heap_oop);
142 if (oopDesc::unsafe_equals(forwarded_oop, heap_oop)) {
143 forwarded_oop = evacuate_object(heap_oop, Thread::current(), evac);
144 }
145 oop prev = atomic_compare_exchange_oop(forwarded_oop, p, heap_oop);
146 if (oopDesc::unsafe_equals(prev, heap_oop)) {
147 return forwarded_oop;
148 } else {
149 return NULL;
150 }
151 }
152 return heap_oop;
153 } else {
154 return NULL;
155 }
156 }
157
158 inline oop ShenandoahHeap::atomic_compare_exchange_oop(oop n, oop* addr, oop c) {
159 return (oop) Atomic::cmpxchg(n, addr, c);
160 }
161
162 inline oop ShenandoahHeap::atomic_compare_exchange_oop(oop n, narrowOop* addr, oop c) {
163 narrowOop cmp = CompressedOops::encode(c);
164 narrowOop val = CompressedOops::encode(n);
165 return CompressedOops::decode((narrowOop) Atomic::cmpxchg(val, addr, cmp));
166 }
167
168 template <class T>
169 inline oop ShenandoahHeap::maybe_update_with_forwarded_not_null(T* p, oop heap_oop) {
170 shenandoah_assert_not_in_cset_loc_except(p, !is_in(p) || is_full_gc_in_progress());
171 shenandoah_assert_correct(p, heap_oop);
172
173 if (in_collection_set(heap_oop)) {
174 oop forwarded_oop = ShenandoahBarrierSet::resolve_forwarded_not_null(heap_oop);
175 if (oopDesc::unsafe_equals(forwarded_oop, heap_oop)) {
176 // E.g. during evacuation.
177 return forwarded_oop;
178 }
179
180 shenandoah_assert_forwarded_except(p, heap_oop, is_full_gc_in_progress());
181 shenandoah_assert_not_in_cset_except(p, forwarded_oop, cancelled_concgc());
182
183 log_develop_trace(gc)("Updating old ref: "PTR_FORMAT" pointing to "PTR_FORMAT" to new ref: "PTR_FORMAT,
184 p2i(p), p2i(heap_oop), p2i(forwarded_oop));
185
186 // If this fails, another thread wrote to p before us, it will be logged in SATB and the
187 // reference be updated later.
188 oop result = atomic_compare_exchange_oop(forwarded_oop, p, heap_oop);
189
190 if (oopDesc::unsafe_equals(result, heap_oop)) { // CAS successful.
191 return forwarded_oop;
192 } else {
193 // Note: we used to assert the following here. This doesn't work because sometimes, during
194 // marking/updating-refs, it can happen that a Java thread beats us with an arraycopy,
195 // which first copies the array, which potentially contains from-space refs, and only afterwards
196 // updates all from-space refs to to-space refs, which leaves a short window where the new array
197 // elements can be from-space.
198 // assert(CompressedOops::is_null(result) ||
199 // oopDesc::unsafe_equals(result, ShenandoahBarrierSet::resolve_oop_static_not_null(result)),
200 // "expect not forwarded");
201 return NULL;
202 }
203 } else {
204 shenandoah_assert_not_forwarded(p, heap_oop);
205 return heap_oop;
206 }
207 }
208
209 inline bool ShenandoahHeap::cancelled_concgc() const {
210 return _cancelled_concgc.get() == CANCELLED;
211 }
212
213 inline bool ShenandoahHeap::check_cancelled_concgc_and_yield(bool sts_active) {
214 if (! (sts_active && ShenandoahSuspendibleWorkers)) {
215 return cancelled_concgc();
216 }
217
218 jbyte prev = _cancelled_concgc.cmpxchg(NOT_CANCELLED, CANCELLABLE);
219 if (prev == CANCELLABLE || prev == NOT_CANCELLED) {
220
221 if (SuspendibleThreadSet::should_yield()) {
222 SuspendibleThreadSet::yield();
223 }
224
225 // Back to CANCELLABLE. The thread that poked NOT_CANCELLED first gets
226 // to restore to CANCELLABLE.
227 if (prev == CANCELLABLE) {
228 _cancelled_concgc.set(CANCELLABLE);
229 }
230 return false;
231 } else {
232 return true;
233 }
234 }
235
236 inline bool ShenandoahHeap::try_cancel_concgc() {
237 while (true) {
238 jbyte prev = _cancelled_concgc.cmpxchg(CANCELLED, CANCELLABLE);
239 if (prev == CANCELLABLE) return true;
240 else if (prev == CANCELLED) return false;
241 assert(ShenandoahSuspendibleWorkers, "should not get here when not using suspendible workers");
242 assert(prev == NOT_CANCELLED, "must be NOT_CANCELLED");
243 {
244 // We need to provide a safepoint here, otherwise we might
245 // spin forever if a SP is pending.
246 ThreadBlockInVM sp(JavaThread::current());
247 SpinPause();
248 }
249 }
250 }
251
252 inline void ShenandoahHeap::clear_cancelled_concgc() {
253 _cancelled_concgc.set(CANCELLABLE);
254 _oom_evac_handler.clear();
255 }
256
257 inline HeapWord* ShenandoahHeap::allocate_from_gclab(Thread* thread, size_t size) {
258 if (UseTLAB) {
259 if (!thread->gclab().is_initialized()) {
260 assert(!thread->is_Java_thread() && !thread->is_Worker_thread(),
261 "Performance: thread should have GCLAB: %s", thread->name());
262 // No GCLABs in this thread, fallback to shared allocation
263 return NULL;
264 }
265 HeapWord* obj = thread->gclab().allocate(size);
266 if (obj != NULL) {
267 return obj;
268 }
269 // Otherwise...
270 return allocate_from_gclab_slow(thread, size);
271 } else {
272 return NULL;
273 }
274 }
275
276 inline oop ShenandoahHeap::evacuate_object(oop p, Thread* thread, bool& evacuated) {
277 evacuated = false;
278
279 if (ShenandoahThreadLocalData::is_oom_during_evac(Thread::current())) {
280 // This thread went through the OOM during evac protocol and it is safe to return
281 // the forward pointer. It must not attempt to evacuate any more.
282 return ShenandoahBarrierSet::resolve_forwarded(p);
283 }
284
285 size_t size_no_fwdptr = (size_t) p->size();
286 size_t size_with_fwdptr = size_no_fwdptr + BrooksPointer::word_size();
287
288 assert(!heap_region_containing(p)->is_humongous(), "never evacuate humongous objects");
289
290 bool alloc_from_gclab = true;
291 HeapWord* filler;
292 #ifdef ASSERT
293
294 assert(ShenandoahThreadLocalData::is_evac_allowed(thread), "must be enclosed in ShenandoahOOMDuringEvacHandler");
295
296 if (ShenandoahOOMDuringEvacALot &&
297 (os::random() & 1) == 0) { // Simulate OOM every ~2nd slow-path call
298 filler = NULL;
299 } else {
300 #endif
301 filler = allocate_from_gclab(thread, size_with_fwdptr);
302 if (filler == NULL) {
303 filler = allocate_memory(size_with_fwdptr, _alloc_shared_gc);
304 alloc_from_gclab = false;
305 }
306 #ifdef ASSERT
307 }
308 #endif
309
310 if (filler == NULL) {
311 concurrent_thread()->handle_alloc_failure_evac(size_with_fwdptr);
312
313 _oom_evac_handler.handle_out_of_memory_during_evacuation();
314
315 return ShenandoahBarrierSet::resolve_forwarded(p);
316 }
317
318 // Copy the object and initialize its forwarding ptr:
319 HeapWord* copy = filler + BrooksPointer::word_size();
320 oop copy_val = oop(copy);
321
322 Copy::aligned_disjoint_words((HeapWord*) p, copy, size_no_fwdptr);
323 BrooksPointer::initialize(oop(copy));
324
325 log_develop_trace(gc, compaction)("Copy object: " PTR_FORMAT " -> " PTR_FORMAT,
326 p2i(p), p2i(copy));
327
328 // Try to install the new forwarding pointer.
329 oop result = BrooksPointer::try_update_forwardee(p, copy_val);
330
331 if (oopDesc::unsafe_equals(result, p)) {
332 // Successfully evacuated. Our copy is now the public one!
333 evacuated = true;
334 log_develop_trace(gc, compaction)("Copy object: " PTR_FORMAT " -> " PTR_FORMAT " succeeded",
335 p2i(p), p2i(copy));
336
337
338 #ifdef ASSERT
339 assert(oopDesc::is_oop(copy_val), "expect oop");
340 assert(p->klass() == copy_val->klass(), "Should have the same class p: "PTR_FORMAT", copy: "PTR_FORMAT,
341 p2i(p), p2i(copy));
342 #endif
343 return copy_val;
344 } else {
345 // Failed to evacuate. We need to deal with the object that is left behind. Since this
346 // new allocation is certainly after TAMS, it will be considered live in the next cycle.
347 // But if it happens to contain references to evacuated regions, those references would
348 // not get updated for this stale copy during this cycle, and we will crash while scanning
349 // it the next cycle.
350 //
351 // For GCLAB allocations, it is enough to rollback the allocation ptr. Either the next
352 // object will overwrite this stale copy, or the filler object on LAB retirement will
353 // do this. For non-GCLAB allocations, we have no way to retract the allocation, and
354 // have to explicitly overwrite the copy with the filler object. With that overwrite,
355 // we have to keep the fwdptr initialized and pointing to our (stale) copy.
356 if (alloc_from_gclab) {
357 thread->gclab().rollback(size_with_fwdptr);
358 } else {
359 fill_with_object(copy, size_no_fwdptr);
360 }
361 log_develop_trace(gc, compaction)("Copy object: " PTR_FORMAT " -> " PTR_FORMAT " failed, use other: " PTR_FORMAT,
362 p2i(p), p2i(copy), p2i(result));
363 return result;
364 }
365 }
366
367 inline bool ShenandoahHeap::requires_marking(const void* entry) const {
368 return ! is_marked_next(oop(entry));
369 }
370
371 bool ShenandoahHeap::region_in_collection_set(size_t region_index) const {
372 assert(collection_set() != NULL, "Sanity");
373 return collection_set()->is_in(region_index);
374 }
375
376 bool ShenandoahHeap::in_collection_set(ShenandoahHeapRegion* r) const {
377 return region_in_collection_set(r->region_number());
378 }
379
380 template <class T>
381 inline bool ShenandoahHeap::in_collection_set(T p) const {
382 HeapWord* obj = (HeapWord*) p;
383 assert(collection_set() != NULL, "Sanity");
384 assert(is_in(obj), "should be in heap");
385
386 return collection_set()->is_in(obj);
387 }
388
389 inline bool ShenandoahHeap::is_stable() const {
390 return _gc_state.is_clear();
391 }
392
393 inline bool ShenandoahHeap::is_idle() const {
394 return _gc_state.is_unset(MARKING | EVACUATION | UPDATEREFS | PARTIAL | TRAVERSAL);
395 }
396
397 inline bool ShenandoahHeap::is_concurrent_mark_in_progress() const {
398 return _gc_state.is_set(MARKING);
399 }
400
401 inline bool ShenandoahHeap::is_concurrent_partial_in_progress() const {
402 return _gc_state.is_set(PARTIAL);
403 }
404
405 inline bool ShenandoahHeap::is_concurrent_traversal_in_progress() const {
406 return _gc_state.is_set(TRAVERSAL);
407 }
408
409 inline bool ShenandoahHeap::is_evacuation_in_progress() const {
410 return _gc_state.is_set(EVACUATION);
411 }
412
413 inline bool ShenandoahHeap::is_gc_in_progress_mask(uint mask) const {
414 return _gc_state.is_set(mask);
415 }
416
417 inline bool ShenandoahHeap::is_degenerated_gc_in_progress() const {
418 return _degenerated_gc_in_progress.is_set();
419 }
420
421 inline bool ShenandoahHeap::is_full_gc_in_progress() const {
422 return _full_gc_in_progress.is_set();
423 }
424
425 inline bool ShenandoahHeap::is_full_gc_move_in_progress() const {
426 return _full_gc_move_in_progress.is_set();
427 }
428
429 inline bool ShenandoahHeap::is_update_refs_in_progress() const {
430 return _gc_state.is_set(UPDATEREFS);
431 }
432
433 inline bool ShenandoahHeap::allocated_after_next_mark_start(HeapWord* addr) const {
434 uintx index = ((uintx) addr) >> ShenandoahHeapRegion::region_size_bytes_shift();
435 HeapWord* top_at_mark_start = _next_top_at_mark_starts[index];
436 bool alloc_after_mark_start = addr >= top_at_mark_start;
437 return alloc_after_mark_start;
438 }
439
440 inline bool ShenandoahHeap::allocated_after_complete_mark_start(HeapWord* addr) const {
441 uintx index = ((uintx) addr) >> ShenandoahHeapRegion::region_size_bytes_shift();
442 HeapWord* top_at_mark_start = _complete_top_at_mark_starts[index];
443 bool alloc_after_mark_start = addr >= top_at_mark_start;
444 return alloc_after_mark_start;
445 }
446
447 template<class T>
448 inline void ShenandoahHeap::marked_object_iterate(ShenandoahHeapRegion* region, T* cl) {
449 marked_object_iterate(region, cl, region->top());
450 }
451
452 template<class T>
453 inline void ShenandoahHeap::marked_object_safe_iterate(ShenandoahHeapRegion* region, T* cl) {
454 marked_object_iterate(region, cl, region->concurrent_iteration_safe_limit());
455 }
456
457 template<class T>
458 inline void ShenandoahHeap::marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit) {
459 assert(BrooksPointer::word_offset() < 0, "skip_delta calculation below assumes the forwarding ptr is before obj");
460 assert(! region->is_humongous_continuation(), "no humongous continuation regions here");
461
462 MarkBitMap* mark_bit_map = _complete_mark_bit_map;
463 HeapWord* tams = complete_top_at_mark_start(region->bottom());
464
465 size_t skip_bitmap_delta = BrooksPointer::word_size() + 1;
466 size_t skip_objsize_delta = BrooksPointer::word_size() /* + actual obj.size() below */;
467 HeapWord* start = region->bottom() + BrooksPointer::word_size();
468 HeapWord* end = MIN2(tams + BrooksPointer::word_size(), region->end());
469
470 // Step 1. Scan below the TAMS based on bitmap data.
471 HeapWord* limit_bitmap = MIN2(limit, tams);
472
473 // Try to scan the initial candidate. If the candidate is above the TAMS, it would
474 // fail the subsequent "< limit_bitmap" checks, and fall through to Step 2.
475 HeapWord* cb = mark_bit_map->getNextMarkedWordAddress(start, end);
476
477 intx dist = ShenandoahMarkScanPrefetch;
478 if (dist > 0) {
479 // Batched scan that prefetches the oop data, anticipating the access to
480 // either header, oop field, or forwarding pointer. Not that we cannot
481 // touch anything in oop, while it still being prefetched to get enough
482 // time for prefetch to work. This is why we try to scan the bitmap linearly,
483 // disregarding the object size. However, since we know forwarding pointer
484 // preceeds the object, we can skip over it. Once we cannot trust the bitmap,
485 // there is no point for prefetching the oop contents, as oop->size() will
486 // touch it prematurely.
487
488 // No variable-length arrays in standard C++, have enough slots to fit
489 // the prefetch distance.
490 static const int SLOT_COUNT = 256;
491 guarantee(dist <= SLOT_COUNT, "adjust slot count");
492 HeapWord* slots[SLOT_COUNT];
493
494 int avail;
495 do {
496 avail = 0;
497 for (int c = 0; (c < dist) && (cb < limit_bitmap); c++) {
498 Prefetch::read(cb, BrooksPointer::byte_offset());
499 slots[avail++] = cb;
500 cb += skip_bitmap_delta;
501 if (cb < limit_bitmap) {
502 cb = mark_bit_map->getNextMarkedWordAddress(cb, limit_bitmap);
503 }
504 }
505
506 for (int c = 0; c < avail; c++) {
507 assert (slots[c] < tams, "only objects below TAMS here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(slots[c]), p2i(tams));
508 assert (slots[c] < limit, "only objects below limit here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(slots[c]), p2i(limit));
509 oop obj = oop(slots[c]);
510 do_object_marked_complete(cl, obj);
511 }
512 } while (avail > 0);
513 } else {
514 while (cb < limit_bitmap) {
515 assert (cb < tams, "only objects below TAMS here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cb), p2i(tams));
516 assert (cb < limit, "only objects below limit here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cb), p2i(limit));
517 oop obj = oop(cb);
518 do_object_marked_complete(cl, obj);
519 cb += skip_bitmap_delta;
520 if (cb < limit_bitmap) {
521 cb = mark_bit_map->getNextMarkedWordAddress(cb, limit_bitmap);
522 }
523 }
524 }
525
526 // Step 2. Accurate size-based traversal, happens past the TAMS.
527 // This restarts the scan at TAMS, which makes sure we traverse all objects,
528 // regardless of what happened at Step 1.
529 HeapWord* cs = tams + BrooksPointer::word_size();
530 while (cs < limit) {
531 assert (cs > tams, "only objects past TAMS here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cs), p2i(tams));
532 assert (cs < limit, "only objects below limit here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cs), p2i(limit));
533 oop obj = oop(cs);
534 int size = obj->size();
535 do_object_marked_complete(cl, obj);
536 cs += size + skip_objsize_delta;
537 }
538 }
539
540 template<class T>
541 inline void ShenandoahHeap::do_object_marked_complete(T* cl, oop obj) {
542 assert(oopDesc::is_oop(obj), "sanity");
543 assert(is_marked_complete(obj), "object expected to be marked");
544 cl->do_object(obj);
545 }
546
547 template <class T>
548 class ShenandoahObjectToOopClosure : public ObjectClosure {
549 T* _cl;
550 public:
551 ShenandoahObjectToOopClosure(T* cl) : _cl(cl) {}
552
553 void do_object(oop obj) {
554 obj->oop_iterate(_cl);
555 }
556 };
557
558 template <class T>
559 class ShenandoahObjectToOopBoundedClosure : public ObjectClosure {
560 T* _cl;
561 MemRegion _bounds;
562 public:
563 ShenandoahObjectToOopBoundedClosure(T* cl, HeapWord* bottom, HeapWord* top) :
564 _cl(cl), _bounds(bottom, top) {}
565
566 void do_object(oop obj) {
567 obj->oop_iterate(_cl, _bounds);
568 }
569 };
570
571 template<class T>
572 inline void ShenandoahHeap::marked_object_oop_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* top) {
573 if (region->is_humongous()) {
574 HeapWord* bottom = region->bottom();
575 if (top > bottom) {
576 region = region->humongous_start_region();
577 ShenandoahObjectToOopBoundedClosure<T> objs(cl, bottom, top);
578 marked_object_iterate(region, &objs);
579 }
580 } else {
581 ShenandoahObjectToOopClosure<T> objs(cl);
582 marked_object_iterate(region, &objs, top);
583 }
584 }
585
586 template<class T>
587 inline void ShenandoahHeap::marked_object_oop_iterate(ShenandoahHeapRegion* region, T* cl) {
588 marked_object_oop_iterate(region, cl, region->top());
589 }
590
591 template<class T>
592 inline void ShenandoahHeap::marked_object_oop_safe_iterate(ShenandoahHeapRegion* region, T* cl) {
593 marked_object_oop_iterate(region, cl, region->concurrent_iteration_safe_limit());
594 }
595
596 inline ShenandoahHeapRegion* const ShenandoahHeap::get_region(size_t region_idx) const {
597 if (region_idx >= _num_regions) {
598 return NULL;
599 } else {
600 return _regions[region_idx];
601 }
602 }
603
604 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAP_INLINE_HPP