1 /* 2 * Copyright (c) 2015, 2020, Red Hat, Inc. 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_GC_SHENANDOAH_SHENANDOAHHEAP_INLINE_HPP 26 #define SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_INLINE_HPP 27 28 #include "gc/shenandoah/shenandoahHeap.hpp" 29 30 #include "classfile/javaClasses.inline.hpp" 31 #include "gc/shared/markBitMap.inline.hpp" 32 #include "gc/shared/threadLocalAllocBuffer.inline.hpp" 33 #include "gc/shared/continuationGCSupport.inline.hpp" 34 #include "gc/shared/suspendibleThreadSet.hpp" 35 #include "gc/shared/tlab_globals.hpp" 36 #include "gc/shenandoah/shenandoahAsserts.hpp" 37 #include "gc/shenandoah/shenandoahBarrierSet.inline.hpp" 38 #include "gc/shenandoah/shenandoahCollectionSet.inline.hpp" 39 #include "gc/shenandoah/shenandoahForwarding.inline.hpp" 40 #include "gc/shenandoah/shenandoahWorkGroup.hpp" 41 #include "gc/shenandoah/shenandoahHeapRegionSet.inline.hpp" 42 #include "gc/shenandoah/shenandoahHeapRegion.inline.hpp" 43 #include "gc/shenandoah/shenandoahControlThread.hpp" 44 #include "gc/shenandoah/shenandoahMarkingContext.inline.hpp" 45 #include "gc/shenandoah/shenandoahObjectUtils.inline.hpp" 46 #include "gc/shenandoah/shenandoahThreadLocalData.hpp" 47 #include "oops/compressedOops.inline.hpp" 48 #include "oops/oop.inline.hpp" 49 #include "runtime/atomic.hpp" 50 #include "runtime/javaThread.hpp" 51 #include "runtime/prefetch.inline.hpp" 52 #include "utilities/copy.hpp" 53 #include "utilities/globalDefinitions.hpp" 54 55 inline ShenandoahHeap* ShenandoahHeap::heap() { 56 return named_heap<ShenandoahHeap>(CollectedHeap::Shenandoah); 57 } 58 59 inline ShenandoahHeapRegion* ShenandoahRegionIterator::next() { 60 size_t new_index = Atomic::add(&_index, (size_t) 1, memory_order_relaxed); 61 // get_region() provides the bounds-check and returns null on OOB. 62 return _heap->get_region(new_index - 1); 63 } 64 65 inline bool ShenandoahHeap::has_forwarded_objects() const { 66 return _gc_state.is_set(HAS_FORWARDED); 67 } 68 69 inline WorkerThreads* ShenandoahHeap::workers() const { 70 return _workers; 71 } 72 73 inline WorkerThreads* ShenandoahHeap::safepoint_workers() { 74 return _safepoint_workers; 75 } 76 77 inline size_t ShenandoahHeap::heap_region_index_containing(const void* addr) const { 78 uintptr_t region_start = ((uintptr_t) addr); 79 uintptr_t index = (region_start - (uintptr_t) base()) >> ShenandoahHeapRegion::region_size_bytes_shift(); 80 assert(index < num_regions(), "Region index is in bounds: " PTR_FORMAT, p2i(addr)); 81 return index; 82 } 83 84 inline ShenandoahHeapRegion* const ShenandoahHeap::heap_region_containing(const void* addr) const { 85 size_t index = heap_region_index_containing(addr); 86 ShenandoahHeapRegion* const result = get_region(index); 87 assert(addr >= result->bottom() && addr < result->end(), "Heap region contains the address: " PTR_FORMAT, p2i(addr)); 88 return result; 89 } 90 91 inline void ShenandoahHeap::enter_evacuation(Thread* t) { 92 _oom_evac_handler.enter_evacuation(t); 93 } 94 95 inline void ShenandoahHeap::leave_evacuation(Thread* t) { 96 _oom_evac_handler.leave_evacuation(t); 97 } 98 99 template <class T> 100 inline void ShenandoahHeap::update_with_forwarded(T* p) { 101 T o = RawAccess<>::oop_load(p); 102 if (!CompressedOops::is_null(o)) { 103 oop obj = CompressedOops::decode_not_null(o); 104 if (in_collection_set(obj)) { 105 // Corner case: when evacuation fails, there are objects in collection 106 // set that are not really forwarded. We can still go and try and update them 107 // (uselessly) to simplify the common path. 108 shenandoah_assert_forwarded_except(p, obj, cancelled_gc()); 109 oop fwd = ShenandoahBarrierSet::resolve_forwarded_not_null(obj); 110 shenandoah_assert_not_in_cset_except(p, fwd, cancelled_gc()); 111 112 // Unconditionally store the update: no concurrent updates expected. 113 RawAccess<IS_NOT_NULL>::oop_store(p, fwd); 114 } 115 } 116 } 117 118 template <class T> 119 inline void ShenandoahHeap::conc_update_with_forwarded(T* p) { 120 T o = RawAccess<>::oop_load(p); 121 if (!CompressedOops::is_null(o)) { 122 oop obj = CompressedOops::decode_not_null(o); 123 if (in_collection_set(obj)) { 124 // Corner case: when evacuation fails, there are objects in collection 125 // set that are not really forwarded. We can still go and try CAS-update them 126 // (uselessly) to simplify the common path. 127 shenandoah_assert_forwarded_except(p, obj, cancelled_gc()); 128 oop fwd = ShenandoahBarrierSet::resolve_forwarded_not_null(obj); 129 shenandoah_assert_not_in_cset_except(p, fwd, cancelled_gc()); 130 131 // Sanity check: we should not be updating the cset regions themselves, 132 // unless we are recovering from the evacuation failure. 133 shenandoah_assert_not_in_cset_loc_except(p, !is_in(p) || cancelled_gc()); 134 135 // Either we succeed in updating the reference, or something else gets in our way. 136 // We don't care if that is another concurrent GC update, or another mutator update. 137 atomic_update_oop(fwd, p, obj); 138 } 139 } 140 } 141 142 // Atomic updates of heap location. This is only expected to work with updating the same 143 // logical object with its forwardee. The reason why we need stronger-than-relaxed memory 144 // ordering has to do with coordination with GC barriers and mutator accesses. 145 // 146 // In essence, stronger CAS access is required to maintain the transitive chains that mutator 147 // accesses build by themselves. To illustrate this point, consider the following example. 148 // 149 // Suppose "o" is the object that has a field "x" and the reference to "o" is stored 150 // to field at "addr", which happens to be Java volatile field. Normally, the accesses to volatile 151 // field at "addr" would be matched with release/acquire barriers. This changes when GC moves 152 // the object under mutator feet. 153 // 154 // Thread 1 (Java) 155 // // --- previous access starts here 156 // ... 157 // T1.1: store(&o.x, 1, mo_relaxed) 158 // T1.2: store(&addr, o, mo_release) // volatile store 159 // 160 // // --- new access starts here 161 // // LRB: copy and install the new copy to fwdptr 162 // T1.3: var copy = copy(o) 163 // T1.4: cas(&fwd, t, copy, mo_release) // pointer-mediated publication 164 // <access continues> 165 // 166 // Thread 2 (GC updater) 167 // T2.1: var f = load(&fwd, mo_{consume|acquire}) // pointer-mediated acquisition 168 // T2.2: cas(&addr, o, f, mo_release) // this method 169 // 170 // Thread 3 (Java) 171 // T3.1: var o = load(&addr, mo_acquire) // volatile read 172 // T3.2: if (o != null) 173 // T3.3: var r = load(&o.x, mo_relaxed) 174 // 175 // r is guaranteed to contain "1". 176 // 177 // Without GC involvement, there is synchronizes-with edge from T1.2 to T3.1, 178 // which guarantees this. With GC involvement, when LRB copies the object and 179 // another thread updates the reference to it, we need to have the transitive edge 180 // from T1.4 to T2.1 (that one is guaranteed by forwarding accesses), plus the edge 181 // from T2.2 to T3.1 (which is brought by this CAS). 182 // 183 // Note that we do not need to "acquire" in these methods, because we do not read the 184 // failure witnesses contents on any path, and "release" is enough. 185 // 186 187 inline void ShenandoahHeap::atomic_update_oop(oop update, oop* addr, oop compare) { 188 assert(is_aligned(addr, HeapWordSize), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 189 Atomic::cmpxchg(addr, compare, update, memory_order_release); 190 } 191 192 inline void ShenandoahHeap::atomic_update_oop(oop update, narrowOop* addr, narrowOop compare) { 193 assert(is_aligned(addr, sizeof(narrowOop)), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 194 narrowOop u = CompressedOops::encode(update); 195 Atomic::cmpxchg(addr, compare, u, memory_order_release); 196 } 197 198 inline void ShenandoahHeap::atomic_update_oop(oop update, narrowOop* addr, oop compare) { 199 assert(is_aligned(addr, sizeof(narrowOop)), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 200 narrowOop c = CompressedOops::encode(compare); 201 narrowOop u = CompressedOops::encode(update); 202 Atomic::cmpxchg(addr, c, u, memory_order_release); 203 } 204 205 inline bool ShenandoahHeap::atomic_update_oop_check(oop update, oop* addr, oop compare) { 206 assert(is_aligned(addr, HeapWordSize), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 207 return (oop) Atomic::cmpxchg(addr, compare, update, memory_order_release) == compare; 208 } 209 210 inline bool ShenandoahHeap::atomic_update_oop_check(oop update, narrowOop* addr, narrowOop compare) { 211 assert(is_aligned(addr, sizeof(narrowOop)), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 212 narrowOop u = CompressedOops::encode(update); 213 return (narrowOop) Atomic::cmpxchg(addr, compare, u, memory_order_release) == compare; 214 } 215 216 inline bool ShenandoahHeap::atomic_update_oop_check(oop update, narrowOop* addr, oop compare) { 217 assert(is_aligned(addr, sizeof(narrowOop)), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 218 narrowOop c = CompressedOops::encode(compare); 219 narrowOop u = CompressedOops::encode(update); 220 return CompressedOops::decode(Atomic::cmpxchg(addr, c, u, memory_order_release)) == compare; 221 } 222 223 // The memory ordering discussion above does not apply for methods that store nulls: 224 // then, there is no transitive reads in mutator (as we see nulls), and we can do 225 // relaxed memory ordering there. 226 227 inline void ShenandoahHeap::atomic_clear_oop(oop* addr, oop compare) { 228 assert(is_aligned(addr, HeapWordSize), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 229 Atomic::cmpxchg(addr, compare, oop(), memory_order_relaxed); 230 } 231 232 inline void ShenandoahHeap::atomic_clear_oop(narrowOop* addr, oop compare) { 233 assert(is_aligned(addr, sizeof(narrowOop)), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 234 narrowOop cmp = CompressedOops::encode(compare); 235 Atomic::cmpxchg(addr, cmp, narrowOop(), memory_order_relaxed); 236 } 237 238 inline void ShenandoahHeap::atomic_clear_oop(narrowOop* addr, narrowOop compare) { 239 assert(is_aligned(addr, sizeof(narrowOop)), "Address should be aligned: " PTR_FORMAT, p2i(addr)); 240 Atomic::cmpxchg(addr, compare, narrowOop(), memory_order_relaxed); 241 } 242 243 inline bool ShenandoahHeap::cancelled_gc() const { 244 return _cancelled_gc.get() == CANCELLED; 245 } 246 247 inline bool ShenandoahHeap::check_cancelled_gc_and_yield(bool sts_active) { 248 if (! (sts_active && ShenandoahSuspendibleWorkers)) { 249 return cancelled_gc(); 250 } 251 252 jbyte prev = _cancelled_gc.cmpxchg(NOT_CANCELLED, CANCELLABLE); 253 if (prev == CANCELLABLE || prev == NOT_CANCELLED) { 254 if (SuspendibleThreadSet::should_yield()) { 255 SuspendibleThreadSet::yield(); 256 } 257 258 // Back to CANCELLABLE. The thread that poked NOT_CANCELLED first gets 259 // to restore to CANCELLABLE. 260 if (prev == CANCELLABLE) { 261 _cancelled_gc.set(CANCELLABLE); 262 } 263 return false; 264 } else { 265 return true; 266 } 267 } 268 269 inline void ShenandoahHeap::clear_cancelled_gc() { 270 _cancelled_gc.set(CANCELLABLE); 271 _oom_evac_handler.clear(); 272 } 273 274 inline HeapWord* ShenandoahHeap::allocate_from_gclab(Thread* thread, size_t size) { 275 assert(UseTLAB, "TLABs should be enabled"); 276 277 PLAB* gclab = ShenandoahThreadLocalData::gclab(thread); 278 if (gclab == nullptr) { 279 assert(!thread->is_Java_thread() && !thread->is_Worker_thread(), 280 "Performance: thread should have GCLAB: %s", thread->name()); 281 // No GCLABs in this thread, fallback to shared allocation 282 return nullptr; 283 } 284 HeapWord* obj = gclab->allocate(size); 285 if (obj != nullptr) { 286 return obj; 287 } 288 // Otherwise... 289 return allocate_from_gclab_slow(thread, size); 290 } 291 292 inline oop ShenandoahHeap::evacuate_object(oop p, Thread* thread) { 293 if (ShenandoahThreadLocalData::is_oom_during_evac(Thread::current())) { 294 // This thread went through the OOM during evac protocol and it is safe to return 295 // the forward pointer. It must not attempt to evacuate any more. 296 return ShenandoahBarrierSet::resolve_forwarded(p); 297 } 298 299 assert(ShenandoahThreadLocalData::is_evac_allowed(thread), "must be enclosed in oom-evac scope"); 300 301 size_t size = ShenandoahObjectUtils::size(p); 302 303 assert(!heap_region_containing(p)->is_humongous(), "never evacuate humongous objects"); 304 305 bool alloc_from_gclab = true; 306 HeapWord* copy = nullptr; 307 308 #ifdef ASSERT 309 if (ShenandoahOOMDuringEvacALot && 310 (os::random() & 1) == 0) { // Simulate OOM every ~2nd slow-path call 311 copy = nullptr; 312 } else { 313 #endif 314 if (UseTLAB) { 315 copy = allocate_from_gclab(thread, size); 316 } 317 if (copy == nullptr) { 318 ShenandoahAllocRequest req = ShenandoahAllocRequest::for_shared_gc(size); 319 copy = allocate_memory(req); 320 alloc_from_gclab = false; 321 } 322 #ifdef ASSERT 323 } 324 #endif 325 326 if (copy == nullptr) { 327 control_thread()->handle_alloc_failure_evac(size); 328 329 _oom_evac_handler.handle_out_of_memory_during_evacuation(); 330 331 return ShenandoahBarrierSet::resolve_forwarded(p); 332 } 333 334 // Copy the object: 335 Copy::aligned_disjoint_words(cast_from_oop<HeapWord*>(p), copy, size); 336 337 // Try to install the new forwarding pointer. 338 oop copy_val = cast_to_oop(copy); 339 if (!copy_val->mark().is_marked()) { 340 // If we copied a mark-word that indicates 'forwarded' state, then 341 // another thread beat us, and this new copy will never be published. 342 // ContinuationGCSupport would get a corrupt Klass* in that case, 343 // so don't even attempt it. 344 ContinuationGCSupport::relativize_stack_chunk(copy_val); 345 } 346 oop result = ShenandoahForwarding::try_update_forwardee(p, copy_val); 347 if (result == copy_val) { 348 // Successfully evacuated. Our copy is now the public one! 349 shenandoah_assert_correct(nullptr, copy_val); 350 return copy_val; 351 } else { 352 // Failed to evacuate. We need to deal with the object that is left behind. Since this 353 // new allocation is certainly after TAMS, it will be considered live in the next cycle. 354 // But if it happens to contain references to evacuated regions, those references would 355 // not get updated for this stale copy during this cycle, and we will crash while scanning 356 // it the next cycle. 357 // 358 // For GCLAB allocations, it is enough to rollback the allocation ptr. Either the next 359 // object will overwrite this stale copy, or the filler object on LAB retirement will 360 // do this. For non-GCLAB allocations, we have no way to retract the allocation, and 361 // have to explicitly overwrite the copy with the filler object. With that overwrite, 362 // we have to keep the fwdptr initialized and pointing to our (stale) copy. 363 if (alloc_from_gclab) { 364 ShenandoahThreadLocalData::gclab(thread)->undo_allocation(copy, size); 365 } else { 366 fill_with_object(copy, size); 367 shenandoah_assert_correct(nullptr, copy_val); 368 } 369 shenandoah_assert_correct(nullptr, result); 370 return result; 371 } 372 } 373 374 inline bool ShenandoahHeap::requires_marking(const void* entry) const { 375 oop obj = cast_to_oop(entry); 376 return !_marking_context->is_marked_strong(obj); 377 } 378 379 inline bool ShenandoahHeap::in_collection_set(oop p) const { 380 assert(collection_set() != nullptr, "Sanity"); 381 return collection_set()->is_in(p); 382 } 383 384 inline bool ShenandoahHeap::in_collection_set_loc(void* p) const { 385 assert(collection_set() != nullptr, "Sanity"); 386 return collection_set()->is_in_loc(p); 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); 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_evacuation_in_progress() const { 402 return _gc_state.is_set(EVACUATION); 403 } 404 405 inline bool ShenandoahHeap::is_gc_in_progress_mask(uint mask) const { 406 return _gc_state.is_set(mask); 407 } 408 409 inline bool ShenandoahHeap::is_degenerated_gc_in_progress() const { 410 return _degenerated_gc_in_progress.is_set(); 411 } 412 413 inline bool ShenandoahHeap::is_full_gc_in_progress() const { 414 return _full_gc_in_progress.is_set(); 415 } 416 417 inline bool ShenandoahHeap::is_full_gc_move_in_progress() const { 418 return _full_gc_move_in_progress.is_set(); 419 } 420 421 inline bool ShenandoahHeap::is_update_refs_in_progress() const { 422 return _gc_state.is_set(UPDATEREFS); 423 } 424 425 inline bool ShenandoahHeap::is_stw_gc_in_progress() const { 426 return is_full_gc_in_progress() || is_degenerated_gc_in_progress(); 427 } 428 429 inline bool ShenandoahHeap::is_concurrent_strong_root_in_progress() const { 430 return _concurrent_strong_root_in_progress.is_set(); 431 } 432 433 inline bool ShenandoahHeap::is_concurrent_weak_root_in_progress() const { 434 return _gc_state.is_set(WEAK_ROOTS); 435 } 436 437 template<class T> 438 inline void ShenandoahHeap::marked_object_iterate(ShenandoahHeapRegion* region, T* cl) { 439 marked_object_iterate(region, cl, region->top()); 440 } 441 442 template<class T> 443 inline void ShenandoahHeap::marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit) { 444 assert(! region->is_humongous_continuation(), "no humongous continuation regions here"); 445 446 ShenandoahMarkingContext* const ctx = complete_marking_context(); 447 assert(ctx->is_complete(), "sanity"); 448 449 HeapWord* tams = ctx->top_at_mark_start(region); 450 451 size_t skip_bitmap_delta = 1; 452 HeapWord* start = region->bottom(); 453 HeapWord* end = MIN2(tams, region->end()); 454 455 // Step 1. Scan below the TAMS based on bitmap data. 456 HeapWord* limit_bitmap = MIN2(limit, tams); 457 458 // Try to scan the initial candidate. If the candidate is above the TAMS, it would 459 // fail the subsequent "< limit_bitmap" checks, and fall through to Step 2. 460 HeapWord* cb = ctx->get_next_marked_addr(start, end); 461 462 intx dist = ShenandoahMarkScanPrefetch; 463 if (dist > 0) { 464 // Batched scan that prefetches the oop data, anticipating the access to 465 // either header, oop field, or forwarding pointer. Not that we cannot 466 // touch anything in oop, while it still being prefetched to get enough 467 // time for prefetch to work. This is why we try to scan the bitmap linearly, 468 // disregarding the object size. However, since we know forwarding pointer 469 // precedes the object, we can skip over it. Once we cannot trust the bitmap, 470 // there is no point for prefetching the oop contents, as oop->size() will 471 // touch it prematurely. 472 473 // No variable-length arrays in standard C++, have enough slots to fit 474 // the prefetch distance. 475 static const int SLOT_COUNT = 256; 476 guarantee(dist <= SLOT_COUNT, "adjust slot count"); 477 HeapWord* slots[SLOT_COUNT]; 478 479 int avail; 480 do { 481 avail = 0; 482 for (int c = 0; (c < dist) && (cb < limit_bitmap); c++) { 483 Prefetch::read(cb, oopDesc::mark_offset_in_bytes()); 484 slots[avail++] = cb; 485 cb += skip_bitmap_delta; 486 if (cb < limit_bitmap) { 487 cb = ctx->get_next_marked_addr(cb, limit_bitmap); 488 } 489 } 490 491 for (int c = 0; c < avail; c++) { 492 assert (slots[c] < tams, "only objects below TAMS here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(slots[c]), p2i(tams)); 493 assert (slots[c] < limit, "only objects below limit here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(slots[c]), p2i(limit)); 494 oop obj = cast_to_oop(slots[c]); 495 assert(oopDesc::is_oop(obj), "sanity"); 496 assert(ctx->is_marked(obj), "object expected to be marked"); 497 cl->do_object(obj); 498 } 499 } while (avail > 0); 500 } else { 501 while (cb < limit_bitmap) { 502 assert (cb < tams, "only objects below TAMS here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cb), p2i(tams)); 503 assert (cb < limit, "only objects below limit here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cb), p2i(limit)); 504 oop obj = cast_to_oop(cb); 505 assert(oopDesc::is_oop(obj), "sanity"); 506 assert(ctx->is_marked(obj), "object expected to be marked"); 507 cl->do_object(obj); 508 cb += skip_bitmap_delta; 509 if (cb < limit_bitmap) { 510 cb = ctx->get_next_marked_addr(cb, limit_bitmap); 511 } 512 } 513 } 514 515 // Step 2. Accurate size-based traversal, happens past the TAMS. 516 // This restarts the scan at TAMS, which makes sure we traverse all objects, 517 // regardless of what happened at Step 1. 518 HeapWord* cs = tams; 519 while (cs < limit) { 520 assert (cs >= tams, "only objects past TAMS here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cs), p2i(tams)); 521 assert (cs < limit, "only objects below limit here: " PTR_FORMAT " (" PTR_FORMAT ")", p2i(cs), p2i(limit)); 522 oop obj = cast_to_oop(cs); 523 assert(oopDesc::is_oop(obj), "sanity"); 524 assert(ctx->is_marked(obj), "object expected to be marked"); 525 size_t size = ShenandoahObjectUtils::size(obj); 526 cl->do_object(obj); 527 cs += size; 528 } 529 } 530 531 template <class T> 532 class ShenandoahObjectToOopClosure : public ObjectClosure { 533 T* _cl; 534 public: 535 ShenandoahObjectToOopClosure(T* cl) : _cl(cl) {} 536 537 void do_object(oop obj) { 538 obj->oop_iterate(_cl); 539 } 540 }; 541 542 template <class T> 543 class ShenandoahObjectToOopBoundedClosure : public ObjectClosure { 544 T* _cl; 545 MemRegion _bounds; 546 public: 547 ShenandoahObjectToOopBoundedClosure(T* cl, HeapWord* bottom, HeapWord* top) : 548 _cl(cl), _bounds(bottom, top) {} 549 550 void do_object(oop obj) { 551 obj->oop_iterate(_cl, _bounds); 552 } 553 }; 554 555 template<class T> 556 inline void ShenandoahHeap::marked_object_oop_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* top) { 557 if (region->is_humongous()) { 558 HeapWord* bottom = region->bottom(); 559 if (top > bottom) { 560 region = region->humongous_start_region(); 561 ShenandoahObjectToOopBoundedClosure<T> objs(cl, bottom, top); 562 marked_object_iterate(region, &objs); 563 } 564 } else { 565 ShenandoahObjectToOopClosure<T> objs(cl); 566 marked_object_iterate(region, &objs, top); 567 } 568 } 569 570 inline ShenandoahHeapRegion* const ShenandoahHeap::get_region(size_t region_idx) const { 571 if (region_idx < _num_regions) { 572 return _regions[region_idx]; 573 } else { 574 return nullptr; 575 } 576 } 577 578 inline void ShenandoahHeap::mark_complete_marking_context() { 579 _marking_context->mark_complete(); 580 } 581 582 inline void ShenandoahHeap::mark_incomplete_marking_context() { 583 _marking_context->mark_incomplete(); 584 } 585 586 inline ShenandoahMarkingContext* ShenandoahHeap::complete_marking_context() const { 587 assert (_marking_context->is_complete()," sanity"); 588 return _marking_context; 589 } 590 591 inline ShenandoahMarkingContext* ShenandoahHeap::marking_context() const { 592 return _marking_context; 593 } 594 595 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_INLINE_HPP