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