| /* |
| * Copyright (C) 2011 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_SPACE_SPACE_H_ |
| #define ART_RUNTIME_GC_SPACE_SPACE_H_ |
| |
| #include <string> |
| |
| #include "UniquePtr.h" |
| #include "base/macros.h" |
| #include "base/mutex.h" |
| #include "gc/accounting/space_bitmap.h" |
| #include "globals.h" |
| #include "image.h" |
| #include "mem_map.h" |
| |
| namespace art { |
| namespace mirror { |
| class Object; |
| } // namespace mirror |
| |
| namespace gc { |
| |
| namespace accounting { |
| class SpaceBitmap; |
| } // namespace accounting |
| |
| class Heap; |
| |
| namespace space { |
| |
| class AllocSpace; |
| class BumpPointerSpace; |
| class ContinuousSpace; |
| class DiscontinuousSpace; |
| class MallocSpace; |
| class DlMallocSpace; |
| class RosAllocSpace; |
| class ImageSpace; |
| class LargeObjectSpace; |
| |
| static constexpr bool kDebugSpaces = kIsDebugBuild; |
| |
| // See Space::GetGcRetentionPolicy. |
| enum GcRetentionPolicy { |
| // Objects are retained forever with this policy for a space. |
| kGcRetentionPolicyNeverCollect, |
| // Every GC cycle will attempt to collect objects in this space. |
| kGcRetentionPolicyAlwaysCollect, |
| // Objects will be considered for collection only in "full" GC cycles, ie faster partial |
| // collections won't scan these areas such as the Zygote. |
| kGcRetentionPolicyFullCollect, |
| }; |
| std::ostream& operator<<(std::ostream& os, const GcRetentionPolicy& policy); |
| |
| enum SpaceType { |
| kSpaceTypeImageSpace, |
| kSpaceTypeAllocSpace, |
| kSpaceTypeZygoteSpace, |
| kSpaceTypeBumpPointerSpace, |
| kSpaceTypeLargeObjectSpace, |
| }; |
| std::ostream& operator<<(std::ostream& os, const SpaceType& space_type); |
| |
| // A space contains memory allocated for managed objects. |
| class Space { |
| public: |
| // Dump space. Also key method for C++ vtables. |
| virtual void Dump(std::ostream& os) const; |
| |
| // Name of the space. May vary, for example before/after the Zygote fork. |
| const char* GetName() const { |
| return name_.c_str(); |
| } |
| |
| // The policy of when objects are collected associated with this space. |
| GcRetentionPolicy GetGcRetentionPolicy() const { |
| return gc_retention_policy_; |
| } |
| |
| // Does the space support allocation? |
| virtual bool CanAllocateInto() const { |
| return true; |
| } |
| |
| // Is the given object contained within this space? |
| virtual bool Contains(const mirror::Object* obj) const = 0; |
| |
| // The kind of space this: image, alloc, zygote, large object. |
| virtual SpaceType GetType() const = 0; |
| |
| // Is this an image space, ie one backed by a memory mapped image file. |
| bool IsImageSpace() const { |
| return GetType() == kSpaceTypeImageSpace; |
| } |
| ImageSpace* AsImageSpace(); |
| |
| // Is this a dlmalloc backed allocation space? |
| bool IsMallocSpace() const { |
| SpaceType type = GetType(); |
| return type == kSpaceTypeAllocSpace || type == kSpaceTypeZygoteSpace; |
| } |
| MallocSpace* AsMallocSpace(); |
| |
| virtual bool IsDlMallocSpace() const { |
| return false; |
| } |
| virtual DlMallocSpace* AsDlMallocSpace() { |
| LOG(FATAL) << "Unreachable"; |
| return NULL; |
| } |
| virtual bool IsRosAllocSpace() const { |
| return false; |
| } |
| virtual RosAllocSpace* AsRosAllocSpace() { |
| LOG(FATAL) << "Unreachable"; |
| return NULL; |
| } |
| |
| // Is this the space allocated into by the Zygote and no-longer in use? |
| bool IsZygoteSpace() const { |
| return GetType() == kSpaceTypeZygoteSpace; |
| } |
| |
| // Is this space a bump pointer space? |
| bool IsBumpPointerSpace() const { |
| return GetType() == kSpaceTypeBumpPointerSpace; |
| } |
| virtual BumpPointerSpace* AsBumpPointerSpace() { |
| LOG(FATAL) << "Unreachable"; |
| return NULL; |
| } |
| |
| // Does this space hold large objects and implement the large object space abstraction? |
| bool IsLargeObjectSpace() const { |
| return GetType() == kSpaceTypeLargeObjectSpace; |
| } |
| LargeObjectSpace* AsLargeObjectSpace(); |
| |
| virtual bool IsContinuousSpace() const { |
| return false; |
| } |
| ContinuousSpace* AsContinuousSpace(); |
| |
| virtual bool IsDiscontinuousSpace() const { |
| return false; |
| } |
| DiscontinuousSpace* AsDiscontinuousSpace(); |
| |
| virtual bool IsAllocSpace() const { |
| return false; |
| } |
| virtual AllocSpace* AsAllocSpace() { |
| LOG(FATAL) << "Unimplemented"; |
| return nullptr; |
| } |
| |
| virtual ~Space() {} |
| |
| protected: |
| Space(const std::string& name, GcRetentionPolicy gc_retention_policy); |
| |
| void SetGcRetentionPolicy(GcRetentionPolicy gc_retention_policy) { |
| gc_retention_policy_ = gc_retention_policy; |
| } |
| |
| // Name of the space that may vary due to the Zygote fork. |
| std::string name_; |
| |
| protected: |
| // When should objects within this space be reclaimed? Not constant as we vary it in the case |
| // of Zygote forking. |
| GcRetentionPolicy gc_retention_policy_; |
| |
| private: |
| friend class art::gc::Heap; |
| DISALLOW_COPY_AND_ASSIGN(Space); |
| }; |
| std::ostream& operator<<(std::ostream& os, const Space& space); |
| |
| // AllocSpace interface. |
| class AllocSpace { |
| public: |
| // Number of bytes currently allocated. |
| virtual uint64_t GetBytesAllocated() = 0; |
| // Number of objects currently allocated. |
| virtual uint64_t GetObjectsAllocated() = 0; |
| // Number of bytes allocated since the space was created. |
| virtual uint64_t GetTotalBytesAllocated() = 0; |
| // Number of objects allocated since the space was created. |
| virtual uint64_t GetTotalObjectsAllocated() = 0; |
| |
| // Allocate num_bytes without allowing growth. If the allocation |
| // succeeds, the output parameter bytes_allocated will be set to the |
| // actually allocated bytes which is >= num_bytes. |
| virtual mirror::Object* Alloc(Thread* self, size_t num_bytes, size_t* bytes_allocated) = 0; |
| |
| // Return the storage space required by obj. |
| virtual size_t AllocationSize(const mirror::Object* obj) = 0; |
| |
| // Returns how many bytes were freed. |
| virtual size_t Free(Thread* self, mirror::Object* ptr) = 0; |
| |
| // Returns how many bytes were freed. |
| virtual size_t FreeList(Thread* self, size_t num_ptrs, mirror::Object** ptrs) = 0; |
| |
| // Revoke any sort of thread-local buffers that are used to speed up |
| // allocations for the given thread, if the alloc space |
| // implementation uses any. No-op by default. |
| virtual void RevokeThreadLocalBuffers(Thread* /*thread*/) {} |
| |
| // Revoke any sort of thread-local buffers that are used to speed up |
| // allocations for all the threads, if the alloc space |
| // implementation uses any. No-op by default. |
| virtual void RevokeAllThreadLocalBuffers() {} |
| |
| protected: |
| AllocSpace() {} |
| virtual ~AllocSpace() {} |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(AllocSpace); |
| }; |
| |
| // Continuous spaces have bitmaps, and an address range. Although not required, objects within |
| // continuous spaces can be marked in the card table. |
| class ContinuousSpace : public Space { |
| public: |
| // Address at which the space begins. |
| byte* Begin() const { |
| return begin_; |
| } |
| |
| // Current address at which the space ends, which may vary as the space is filled. |
| byte* End() const { |
| return end_; |
| } |
| |
| // The end of the address range covered by the space. |
| byte* Limit() const { |
| return limit_; |
| } |
| |
| // Change the end of the space. Be careful with use since changing the end of a space to an |
| // invalid value may break the GC. |
| void SetEnd(byte* end) { |
| end_ = end; |
| } |
| |
| void SetLimit(byte* limit) { |
| limit_ = limit; |
| } |
| |
| // Current size of space |
| size_t Size() const { |
| return End() - Begin(); |
| } |
| |
| virtual accounting::SpaceBitmap* GetLiveBitmap() const = 0; |
| virtual accounting::SpaceBitmap* GetMarkBitmap() const = 0; |
| |
| // Maximum which the mapped space can grow to. |
| virtual size_t Capacity() const { |
| return Limit() - Begin(); |
| } |
| |
| // Is object within this space? We check to see if the pointer is beyond the end first as |
| // continuous spaces are iterated over from low to high. |
| bool HasAddress(const mirror::Object* obj) const { |
| const byte* byte_ptr = reinterpret_cast<const byte*>(obj); |
| return byte_ptr >= Begin() && byte_ptr < Limit(); |
| } |
| |
| bool Contains(const mirror::Object* obj) const { |
| return HasAddress(obj); |
| } |
| |
| virtual bool IsContinuousSpace() const { |
| return true; |
| } |
| |
| virtual ~ContinuousSpace() {} |
| |
| protected: |
| ContinuousSpace(const std::string& name, GcRetentionPolicy gc_retention_policy, |
| byte* begin, byte* end, byte* limit) : |
| Space(name, gc_retention_policy), begin_(begin), end_(end), limit_(limit) { |
| } |
| |
| // The beginning of the storage for fast access. |
| byte* begin_; |
| |
| // Current end of the space. |
| byte* volatile end_; |
| |
| // Limit of the space. |
| byte* limit_; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(ContinuousSpace); |
| }; |
| |
| // A space where objects may be allocated higgledy-piggledy throughout virtual memory. Currently |
| // the card table can't cover these objects and so the write barrier shouldn't be triggered. This |
| // is suitable for use for large primitive arrays. |
| class DiscontinuousSpace : public Space { |
| public: |
| accounting::SpaceSetMap* GetLiveObjects() const { |
| return live_objects_.get(); |
| } |
| |
| accounting::SpaceSetMap* GetMarkObjects() const { |
| return mark_objects_.get(); |
| } |
| |
| virtual bool IsDiscontinuousSpace() const { |
| return true; |
| } |
| |
| virtual ~DiscontinuousSpace() {} |
| |
| protected: |
| DiscontinuousSpace(const std::string& name, GcRetentionPolicy gc_retention_policy); |
| |
| UniquePtr<accounting::SpaceSetMap> live_objects_; |
| UniquePtr<accounting::SpaceSetMap> mark_objects_; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(DiscontinuousSpace); |
| }; |
| |
| class MemMapSpace : public ContinuousSpace { |
| public: |
| // Size of the space without a limit on its growth. By default this is just the Capacity, but |
| // for the allocation space we support starting with a small heap and then extending it. |
| virtual size_t NonGrowthLimitCapacity() const { |
| return Capacity(); |
| } |
| |
| MemMap* GetMemMap() { |
| return mem_map_.get(); |
| } |
| |
| const MemMap* GetMemMap() const { |
| return mem_map_.get(); |
| } |
| |
| protected: |
| MemMapSpace(const std::string& name, MemMap* mem_map, byte* begin, byte* end, byte* limit, |
| GcRetentionPolicy gc_retention_policy) |
| : ContinuousSpace(name, gc_retention_policy, begin, end, limit), |
| mem_map_(mem_map) { |
| } |
| |
| // Underlying storage of the space |
| UniquePtr<MemMap> mem_map_; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(MemMapSpace); |
| }; |
| |
| // Used by the heap compaction interface to enable copying from one type of alloc space to another. |
| class ContinuousMemMapAllocSpace : public MemMapSpace, public AllocSpace { |
| public: |
| virtual bool IsAllocSpace() const { |
| return true; |
| } |
| |
| virtual AllocSpace* AsAllocSpace() { |
| return this; |
| } |
| |
| virtual void Clear() { |
| LOG(FATAL) << "Unimplemented"; |
| } |
| |
| protected: |
| ContinuousMemMapAllocSpace(const std::string& name, MemMap* mem_map, byte* begin, |
| byte* end, byte* limit, GcRetentionPolicy gc_retention_policy) |
| : MemMapSpace(name, mem_map, begin, end, limit, gc_retention_policy) { |
| } |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(ContinuousMemMapAllocSpace); |
| }; |
| |
| } // namespace space |
| } // namespace gc |
| } // namespace art |
| |
| #endif // ART_RUNTIME_GC_SPACE_SPACE_H_ |