| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ART_RUNTIME_GC_HEAP_INL_H_ |
| #define ART_RUNTIME_GC_HEAP_INL_H_ |
| |
| #include "heap.h" |
| |
| #include "allocation_listener.h" |
| #include "base/quasi_atomic.h" |
| #include "base/time_utils.h" |
| #include "gc/accounting/atomic_stack.h" |
| #include "gc/accounting/card_table-inl.h" |
| #include "gc/allocation_record.h" |
| #include "gc/collector/semi_space.h" |
| #include "gc/space/bump_pointer_space-inl.h" |
| #include "gc/space/dlmalloc_space-inl.h" |
| #include "gc/space/large_object_space.h" |
| #include "gc/space/region_space-inl.h" |
| #include "gc/space/rosalloc_space-inl.h" |
| #include "handle_scope-inl.h" |
| #include "obj_ptr-inl.h" |
| #include "runtime.h" |
| #include "thread-inl.h" |
| #include "verify_object.h" |
| #include "write_barrier-inl.h" |
| |
| namespace art { |
| namespace gc { |
| |
| template <bool kInstrumented, bool kCheckLargeObject, typename PreFenceVisitor> |
| inline mirror::Object* Heap::AllocObjectWithAllocator(Thread* self, |
| ObjPtr<mirror::Class> klass, |
| size_t byte_count, |
| AllocatorType allocator, |
| const PreFenceVisitor& pre_fence_visitor) { |
| if (kIsDebugBuild) { |
| CheckPreconditionsForAllocObject(klass, byte_count); |
| // Since allocation can cause a GC which will need to SuspendAll, make sure all allocations are |
| // done in the runnable state where suspension is expected. |
| CHECK_EQ(self->GetState(), kRunnable); |
| self->AssertThreadSuspensionIsAllowable(); |
| self->AssertNoPendingException(); |
| // Make sure to preserve klass. |
| StackHandleScope<1> hs(self); |
| HandleWrapperObjPtr<mirror::Class> h = hs.NewHandleWrapper(&klass); |
| self->PoisonObjectPointers(); |
| } |
| // Need to check that we aren't the large object allocator since the large object allocation code |
| // path includes this function. If we didn't check we would have an infinite loop. |
| ObjPtr<mirror::Object> obj; |
| if (kCheckLargeObject && UNLIKELY(ShouldAllocLargeObject(klass, byte_count))) { |
| obj = AllocLargeObject<kInstrumented, PreFenceVisitor>(self, &klass, byte_count, |
| pre_fence_visitor); |
| if (obj != nullptr) { |
| return obj.Ptr(); |
| } else { |
| // There should be an OOM exception, since we are retrying, clear it. |
| self->ClearException(); |
| } |
| // If the large object allocation failed, try to use the normal spaces (main space, |
| // non moving space). This can happen if there is significant virtual address space |
| // fragmentation. |
| } |
| // bytes allocated for the (individual) object. |
| size_t bytes_allocated; |
| size_t usable_size; |
| size_t new_num_bytes_allocated = 0; |
| if (IsTLABAllocator(allocator)) { |
| byte_count = RoundUp(byte_count, space::BumpPointerSpace::kAlignment); |
| } |
| // If we have a thread local allocation we don't need to update bytes allocated. |
| if (IsTLABAllocator(allocator) && byte_count <= self->TlabSize()) { |
| obj = self->AllocTlab(byte_count); |
| DCHECK(obj != nullptr) << "AllocTlab can't fail"; |
| obj->SetClass(klass); |
| if (kUseBakerReadBarrier) { |
| obj->AssertReadBarrierState(); |
| } |
| bytes_allocated = byte_count; |
| usable_size = bytes_allocated; |
| pre_fence_visitor(obj, usable_size); |
| QuasiAtomic::ThreadFenceForConstructor(); |
| } else if ( |
| !kInstrumented && allocator == kAllocatorTypeRosAlloc && |
| (obj = rosalloc_space_->AllocThreadLocal(self, byte_count, &bytes_allocated)) != nullptr && |
| LIKELY(obj != nullptr)) { |
| DCHECK(!is_running_on_memory_tool_); |
| obj->SetClass(klass); |
| if (kUseBakerReadBarrier) { |
| obj->AssertReadBarrierState(); |
| } |
| usable_size = bytes_allocated; |
| pre_fence_visitor(obj, usable_size); |
| QuasiAtomic::ThreadFenceForConstructor(); |
| } else { |
| // Bytes allocated that includes bulk thread-local buffer allocations in addition to direct |
| // non-TLAB object allocations. |
| size_t bytes_tl_bulk_allocated = 0u; |
| obj = TryToAllocate<kInstrumented, false>(self, allocator, byte_count, &bytes_allocated, |
| &usable_size, &bytes_tl_bulk_allocated); |
| if (UNLIKELY(obj == nullptr)) { |
| // AllocateInternalWithGc can cause thread suspension, if someone instruments the entrypoints |
| // or changes the allocator in a suspend point here, we need to retry the allocation. |
| obj = AllocateInternalWithGc(self, |
| allocator, |
| kInstrumented, |
| byte_count, |
| &bytes_allocated, |
| &usable_size, |
| &bytes_tl_bulk_allocated, &klass); |
| if (obj == nullptr) { |
| // The only way that we can get a null return if there is no pending exception is if the |
| // allocator or instrumentation changed. |
| if (!self->IsExceptionPending()) { |
| // AllocObject will pick up the new allocator type, and instrumented as true is the safe |
| // default. |
| return AllocObject</*kInstrumented=*/true>(self, |
| klass, |
| byte_count, |
| pre_fence_visitor); |
| } |
| return nullptr; |
| } |
| } |
| DCHECK_GT(bytes_allocated, 0u); |
| DCHECK_GT(usable_size, 0u); |
| obj->SetClass(klass); |
| if (kUseBakerReadBarrier) { |
| obj->AssertReadBarrierState(); |
| } |
| if (collector::SemiSpace::kUseRememberedSet && UNLIKELY(allocator == kAllocatorTypeNonMoving)) { |
| // (Note this if statement will be constant folded away for the |
| // fast-path quick entry points.) Because SetClass() has no write |
| // barrier, if a non-moving space allocation, we need a write |
| // barrier as the class pointer may point to the bump pointer |
| // space (where the class pointer is an "old-to-young" reference, |
| // though rare) under the GSS collector with the remembered set |
| // enabled. We don't need this for kAllocatorTypeRosAlloc/DlMalloc |
| // cases because we don't directly allocate into the main alloc |
| // space (besides promotions) under the SS/GSS collector. |
| WriteBarrier::ForFieldWrite(obj, mirror::Object::ClassOffset(), klass); |
| } |
| pre_fence_visitor(obj, usable_size); |
| QuasiAtomic::ThreadFenceForConstructor(); |
| if (bytes_tl_bulk_allocated > 0) { |
| size_t num_bytes_allocated_before = |
| num_bytes_allocated_.fetch_add(bytes_tl_bulk_allocated, std::memory_order_relaxed); |
| new_num_bytes_allocated = num_bytes_allocated_before + bytes_tl_bulk_allocated; |
| // Only trace when we get an increase in the number of bytes allocated. This happens when |
| // obtaining a new TLAB and isn't often enough to hurt performance according to golem. |
| TraceHeapSize(new_num_bytes_allocated); |
| } |
| } |
| if (kIsDebugBuild && Runtime::Current()->IsStarted()) { |
| CHECK_LE(obj->SizeOf(), usable_size); |
| } |
| // TODO: Deprecate. |
| if (kInstrumented) { |
| if (Runtime::Current()->HasStatsEnabled()) { |
| RuntimeStats* thread_stats = self->GetStats(); |
| ++thread_stats->allocated_objects; |
| thread_stats->allocated_bytes += bytes_allocated; |
| RuntimeStats* global_stats = Runtime::Current()->GetStats(); |
| ++global_stats->allocated_objects; |
| global_stats->allocated_bytes += bytes_allocated; |
| } |
| } else { |
| DCHECK(!Runtime::Current()->HasStatsEnabled()); |
| } |
| if (kInstrumented) { |
| if (IsAllocTrackingEnabled()) { |
| // allocation_records_ is not null since it never becomes null after allocation tracking is |
| // enabled. |
| DCHECK(allocation_records_ != nullptr); |
| allocation_records_->RecordAllocation(self, &obj, bytes_allocated); |
| } |
| AllocationListener* l = alloc_listener_.load(std::memory_order_seq_cst); |
| if (l != nullptr) { |
| // Same as above. We assume that a listener that was once stored will never be deleted. |
| // Otherwise we'd have to perform this under a lock. |
| l->ObjectAllocated(self, &obj, bytes_allocated); |
| } |
| } else { |
| DCHECK(!IsAllocTrackingEnabled()); |
| } |
| if (AllocatorHasAllocationStack(allocator)) { |
| PushOnAllocationStack(self, &obj); |
| } |
| if (kInstrumented) { |
| if (gc_stress_mode_) { |
| CheckGcStressMode(self, &obj); |
| } |
| } else { |
| DCHECK(!gc_stress_mode_); |
| } |
| // IsGcConcurrent() isn't known at compile time so we can optimize by not checking it for |
| // the BumpPointer or TLAB allocators. This is nice since it allows the entire if statement to be |
| // optimized out. And for the other allocators, AllocatorMayHaveConcurrentGC is a constant since |
| // the allocator_type should be constant propagated. |
| if (AllocatorMayHaveConcurrentGC(allocator) && IsGcConcurrent()) { |
| // New_num_bytes_allocated is zero if we didn't update num_bytes_allocated_. |
| // That's fine. |
| CheckConcurrentGCForJava(self, new_num_bytes_allocated, &obj); |
| } |
| VerifyObject(obj); |
| self->VerifyStack(); |
| return obj.Ptr(); |
| } |
| |
| // The size of a thread-local allocation stack in the number of references. |
| static constexpr size_t kThreadLocalAllocationStackSize = 128; |
| |
| inline void Heap::PushOnAllocationStack(Thread* self, ObjPtr<mirror::Object>* obj) { |
| if (kUseThreadLocalAllocationStack) { |
| if (UNLIKELY(!self->PushOnThreadLocalAllocationStack(obj->Ptr()))) { |
| PushOnThreadLocalAllocationStackWithInternalGC(self, obj); |
| } |
| } else if (UNLIKELY(!allocation_stack_->AtomicPushBack(obj->Ptr()))) { |
| PushOnAllocationStackWithInternalGC(self, obj); |
| } |
| } |
| |
| template <bool kInstrumented, typename PreFenceVisitor> |
| inline mirror::Object* Heap::AllocLargeObject(Thread* self, |
| ObjPtr<mirror::Class>* klass, |
| size_t byte_count, |
| const PreFenceVisitor& pre_fence_visitor) { |
| // Save and restore the class in case it moves. |
| StackHandleScope<1> hs(self); |
| auto klass_wrapper = hs.NewHandleWrapper(klass); |
| return AllocObjectWithAllocator<kInstrumented, false, PreFenceVisitor>(self, *klass, byte_count, |
| kAllocatorTypeLOS, |
| pre_fence_visitor); |
| } |
| |
| template <const bool kInstrumented, const bool kGrow> |
| inline mirror::Object* Heap::TryToAllocate(Thread* self, |
| AllocatorType allocator_type, |
| size_t alloc_size, |
| size_t* bytes_allocated, |
| size_t* usable_size, |
| size_t* bytes_tl_bulk_allocated) { |
| if (allocator_type != kAllocatorTypeRegionTLAB && |
| allocator_type != kAllocatorTypeTLAB && |
| allocator_type != kAllocatorTypeRosAlloc && |
| UNLIKELY(IsOutOfMemoryOnAllocation(allocator_type, alloc_size, kGrow))) { |
| return nullptr; |
| } |
| mirror::Object* ret; |
| switch (allocator_type) { |
| case kAllocatorTypeBumpPointer: { |
| DCHECK(bump_pointer_space_ != nullptr); |
| alloc_size = RoundUp(alloc_size, space::BumpPointerSpace::kAlignment); |
| ret = bump_pointer_space_->AllocNonvirtual(alloc_size); |
| if (LIKELY(ret != nullptr)) { |
| *bytes_allocated = alloc_size; |
| *usable_size = alloc_size; |
| *bytes_tl_bulk_allocated = alloc_size; |
| } |
| break; |
| } |
| case kAllocatorTypeRosAlloc: { |
| if (kInstrumented && UNLIKELY(is_running_on_memory_tool_)) { |
| // If running on ASan, we should be using the instrumented path. |
| size_t max_bytes_tl_bulk_allocated = rosalloc_space_->MaxBytesBulkAllocatedFor(alloc_size); |
| if (UNLIKELY(IsOutOfMemoryOnAllocation(allocator_type, |
| max_bytes_tl_bulk_allocated, |
| kGrow))) { |
| return nullptr; |
| } |
| ret = rosalloc_space_->Alloc(self, alloc_size, bytes_allocated, usable_size, |
| bytes_tl_bulk_allocated); |
| } else { |
| DCHECK(!is_running_on_memory_tool_); |
| size_t max_bytes_tl_bulk_allocated = |
| rosalloc_space_->MaxBytesBulkAllocatedForNonvirtual(alloc_size); |
| if (UNLIKELY(IsOutOfMemoryOnAllocation(allocator_type, |
| max_bytes_tl_bulk_allocated, |
| kGrow))) { |
| return nullptr; |
| } |
| if (!kInstrumented) { |
| DCHECK(!rosalloc_space_->CanAllocThreadLocal(self, alloc_size)); |
| } |
| ret = rosalloc_space_->AllocNonvirtual(self, |
| alloc_size, |
| bytes_allocated, |
| usable_size, |
| bytes_tl_bulk_allocated); |
| } |
| break; |
| } |
| case kAllocatorTypeDlMalloc: { |
| if (kInstrumented && UNLIKELY(is_running_on_memory_tool_)) { |
| // If running on ASan, we should be using the instrumented path. |
| ret = dlmalloc_space_->Alloc(self, |
| alloc_size, |
| bytes_allocated, |
| usable_size, |
| bytes_tl_bulk_allocated); |
| } else { |
| DCHECK(!is_running_on_memory_tool_); |
| ret = dlmalloc_space_->AllocNonvirtual(self, |
| alloc_size, |
| bytes_allocated, |
| usable_size, |
| bytes_tl_bulk_allocated); |
| } |
| break; |
| } |
| case kAllocatorTypeNonMoving: { |
| ret = non_moving_space_->Alloc(self, |
| alloc_size, |
| bytes_allocated, |
| usable_size, |
| bytes_tl_bulk_allocated); |
| break; |
| } |
| case kAllocatorTypeLOS: { |
| ret = large_object_space_->Alloc(self, |
| alloc_size, |
| bytes_allocated, |
| usable_size, |
| bytes_tl_bulk_allocated); |
| // Note that the bump pointer spaces aren't necessarily next to |
| // the other continuous spaces like the non-moving alloc space or |
| // the zygote space. |
| DCHECK(ret == nullptr || large_object_space_->Contains(ret)); |
| break; |
| } |
| case kAllocatorTypeRegion: { |
| DCHECK(region_space_ != nullptr); |
| alloc_size = RoundUp(alloc_size, space::RegionSpace::kAlignment); |
| ret = region_space_->AllocNonvirtual<false>(alloc_size, |
| bytes_allocated, |
| usable_size, |
| bytes_tl_bulk_allocated); |
| break; |
| } |
| case kAllocatorTypeTLAB: |
| FALLTHROUGH_INTENDED; |
| case kAllocatorTypeRegionTLAB: { |
| DCHECK_ALIGNED(alloc_size, kObjectAlignment); |
| static_assert(space::RegionSpace::kAlignment == space::BumpPointerSpace::kAlignment, |
| "mismatched alignments"); |
| static_assert(kObjectAlignment == space::BumpPointerSpace::kAlignment, |
| "mismatched alignments"); |
| if (UNLIKELY(self->TlabSize() < alloc_size)) { |
| // kAllocatorTypeTLAB may be the allocator for region space TLAB if the GC is not marking, |
| // that is why the allocator is not passed down. |
| return AllocWithNewTLAB(self, |
| alloc_size, |
| kGrow, |
| bytes_allocated, |
| usable_size, |
| bytes_tl_bulk_allocated); |
| } |
| // The allocation can't fail. |
| ret = self->AllocTlab(alloc_size); |
| DCHECK(ret != nullptr); |
| *bytes_allocated = alloc_size; |
| *bytes_tl_bulk_allocated = 0; // Allocated in an existing buffer. |
| *usable_size = alloc_size; |
| break; |
| } |
| default: { |
| LOG(FATAL) << "Invalid allocator type"; |
| ret = nullptr; |
| } |
| } |
| return ret; |
| } |
| |
| inline bool Heap::ShouldAllocLargeObject(ObjPtr<mirror::Class> c, size_t byte_count) const { |
| // We need to have a zygote space or else our newly allocated large object can end up in the |
| // Zygote resulting in it being prematurely freed. |
| // We can only do this for primitive objects since large objects will not be within the card table |
| // range. This also means that we rely on SetClass not dirtying the object's card. |
| return byte_count >= large_object_threshold_ && (c->IsPrimitiveArray() || c->IsStringClass()); |
| } |
| |
| inline bool Heap::IsOutOfMemoryOnAllocation(AllocatorType allocator_type, |
| size_t alloc_size, |
| bool grow) { |
| size_t old_target = target_footprint_.load(std::memory_order_relaxed); |
| while (true) { |
| size_t old_allocated = num_bytes_allocated_.load(std::memory_order_relaxed); |
| size_t new_footprint = old_allocated + alloc_size; |
| // Tests against heap limits are inherently approximate, since multiple allocations may |
| // race, and this is not atomic with the allocation. |
| if (UNLIKELY(new_footprint <= old_target)) { |
| return false; |
| } else if (UNLIKELY(new_footprint > growth_limit_)) { |
| return true; |
| } |
| // We are between target_footprint_ and growth_limit_ . |
| if (AllocatorMayHaveConcurrentGC(allocator_type) && IsGcConcurrent()) { |
| return false; |
| } else { |
| if (grow) { |
| if (target_footprint_.compare_exchange_weak(/*inout ref*/old_target, new_footprint, |
| std::memory_order_relaxed)) { |
| VlogHeapGrowth(old_target, new_footprint, alloc_size); |
| return false; |
| } // else try again. |
| } else { |
| return true; |
| } |
| } |
| } |
| } |
| |
| inline bool Heap::ShouldConcurrentGCForJava(size_t new_num_bytes_allocated) { |
| // For a Java allocation, we only check whether the number of Java allocated bytes excceeds a |
| // threshold. By not considering native allocation here, we (a) ensure that Java heap bounds are |
| // maintained, and (b) reduce the cost of the check here. |
| return new_num_bytes_allocated >= concurrent_start_bytes_; |
| } |
| |
| inline void Heap::CheckConcurrentGCForJava(Thread* self, |
| size_t new_num_bytes_allocated, |
| ObjPtr<mirror::Object>* obj) { |
| if (UNLIKELY(ShouldConcurrentGCForJava(new_num_bytes_allocated))) { |
| RequestConcurrentGCAndSaveObject(self, false /* force_full */, obj); |
| } |
| } |
| |
| } // namespace gc |
| } // namespace art |
| |
| #endif // ART_RUNTIME_GC_HEAP_INL_H_ |
