| /* |
| * 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. |
| */ |
| |
| #include "heap.h" |
| |
| #define ATRACE_TAG ATRACE_TAG_DALVIK |
| #include <cutils/trace.h> |
| |
| #include <limits> |
| #include <memory> |
| #include <vector> |
| |
| #include "base/allocator.h" |
| #include "base/dumpable.h" |
| #include "base/histogram-inl.h" |
| #include "base/stl_util.h" |
| #include "common_throws.h" |
| #include "cutils/sched_policy.h" |
| #include "debugger.h" |
| #include "gc/accounting/atomic_stack.h" |
| #include "gc/accounting/card_table-inl.h" |
| #include "gc/accounting/heap_bitmap-inl.h" |
| #include "gc/accounting/mod_union_table.h" |
| #include "gc/accounting/mod_union_table-inl.h" |
| #include "gc/accounting/remembered_set.h" |
| #include "gc/accounting/space_bitmap-inl.h" |
| #include "gc/collector/concurrent_copying.h" |
| #include "gc/collector/mark_compact.h" |
| #include "gc/collector/mark_sweep-inl.h" |
| #include "gc/collector/partial_mark_sweep.h" |
| #include "gc/collector/semi_space.h" |
| #include "gc/collector/sticky_mark_sweep.h" |
| #include "gc/reference_processor.h" |
| #include "gc/space/bump_pointer_space.h" |
| #include "gc/space/dlmalloc_space-inl.h" |
| #include "gc/space/image_space.h" |
| #include "gc/space/large_object_space.h" |
| #include "gc/space/rosalloc_space-inl.h" |
| #include "gc/space/space-inl.h" |
| #include "gc/space/zygote_space.h" |
| #include "entrypoints/quick/quick_alloc_entrypoints.h" |
| #include "heap-inl.h" |
| #include "image.h" |
| #include "intern_table.h" |
| #include "mirror/art_field-inl.h" |
| #include "mirror/class-inl.h" |
| #include "mirror/object.h" |
| #include "mirror/object-inl.h" |
| #include "mirror/object_array-inl.h" |
| #include "mirror/reference-inl.h" |
| #include "os.h" |
| #include "reflection.h" |
| #include "runtime.h" |
| #include "ScopedLocalRef.h" |
| #include "scoped_thread_state_change.h" |
| #include "handle_scope-inl.h" |
| #include "thread_list.h" |
| #include "well_known_classes.h" |
| |
| namespace art { |
| |
| namespace gc { |
| |
| static constexpr size_t kCollectorTransitionStressIterations = 0; |
| static constexpr size_t kCollectorTransitionStressWait = 10 * 1000; // Microseconds |
| static constexpr bool kGCALotMode = false; |
| static constexpr size_t kGcAlotInterval = KB; |
| // Minimum amount of remaining bytes before a concurrent GC is triggered. |
| static constexpr size_t kMinConcurrentRemainingBytes = 128 * KB; |
| static constexpr size_t kMaxConcurrentRemainingBytes = 512 * KB; |
| // Sticky GC throughput adjustment, divided by 4. Increasing this causes sticky GC to occur more |
| // relative to partial/full GC. This may be desirable since sticky GCs interfere less with mutator |
| // threads (lower pauses, use less memory bandwidth). |
| static constexpr double kStickyGcThroughputAdjustment = 1.0; |
| // Whether or not we compact the zygote in PreZygoteFork. |
| static constexpr bool kCompactZygote = kMovingCollector; |
| // How many reserve entries are at the end of the allocation stack, these are only needed if the |
| // allocation stack overflows. |
| static constexpr size_t kAllocationStackReserveSize = 1024; |
| // Default mark stack size in bytes. |
| static const size_t kDefaultMarkStackSize = 64 * KB; |
| // Define space name. |
| static const char* kDlMallocSpaceName[2] = {"main dlmalloc space", "main dlmalloc space 1"}; |
| static const char* kRosAllocSpaceName[2] = {"main rosalloc space", "main rosalloc space 1"}; |
| static const char* kMemMapSpaceName[2] = {"main space", "main space 1"}; |
| static constexpr size_t kGSSBumpPointerSpaceCapacity = 32 * MB; |
| |
| Heap::Heap(size_t initial_size, size_t growth_limit, size_t min_free, size_t max_free, |
| double target_utilization, double foreground_heap_growth_multiplier, |
| size_t capacity, size_t non_moving_space_capacity, const std::string& image_file_name, |
| const InstructionSet image_instruction_set, CollectorType foreground_collector_type, |
| CollectorType background_collector_type, |
| space::LargeObjectSpaceType large_object_space_type, size_t large_object_threshold, |
| size_t parallel_gc_threads, size_t conc_gc_threads, bool low_memory_mode, |
| size_t long_pause_log_threshold, size_t long_gc_log_threshold, |
| bool ignore_max_footprint, bool use_tlab, |
| bool verify_pre_gc_heap, bool verify_pre_sweeping_heap, bool verify_post_gc_heap, |
| bool verify_pre_gc_rosalloc, bool verify_pre_sweeping_rosalloc, |
| bool verify_post_gc_rosalloc, bool use_homogeneous_space_compaction_for_oom, |
| uint64_t min_interval_homogeneous_space_compaction_by_oom) |
| : non_moving_space_(nullptr), |
| rosalloc_space_(nullptr), |
| dlmalloc_space_(nullptr), |
| main_space_(nullptr), |
| collector_type_(kCollectorTypeNone), |
| foreground_collector_type_(foreground_collector_type), |
| background_collector_type_(background_collector_type), |
| desired_collector_type_(foreground_collector_type_), |
| heap_trim_request_lock_(nullptr), |
| last_trim_time_(0), |
| heap_transition_or_trim_target_time_(0), |
| heap_trim_request_pending_(false), |
| parallel_gc_threads_(parallel_gc_threads), |
| conc_gc_threads_(conc_gc_threads), |
| low_memory_mode_(low_memory_mode), |
| long_pause_log_threshold_(long_pause_log_threshold), |
| long_gc_log_threshold_(long_gc_log_threshold), |
| ignore_max_footprint_(ignore_max_footprint), |
| zygote_creation_lock_("zygote creation lock", kZygoteCreationLock), |
| zygote_space_(nullptr), |
| large_object_threshold_(large_object_threshold), |
| collector_type_running_(kCollectorTypeNone), |
| last_gc_type_(collector::kGcTypeNone), |
| next_gc_type_(collector::kGcTypePartial), |
| capacity_(capacity), |
| growth_limit_(growth_limit), |
| max_allowed_footprint_(initial_size), |
| native_footprint_gc_watermark_(initial_size), |
| native_need_to_run_finalization_(false), |
| // Initially assume we perceive jank in case the process state is never updated. |
| process_state_(kProcessStateJankPerceptible), |
| concurrent_start_bytes_(std::numeric_limits<size_t>::max()), |
| total_bytes_freed_ever_(0), |
| total_objects_freed_ever_(0), |
| num_bytes_allocated_(0), |
| native_bytes_allocated_(0), |
| verify_missing_card_marks_(false), |
| verify_system_weaks_(false), |
| verify_pre_gc_heap_(verify_pre_gc_heap), |
| verify_pre_sweeping_heap_(verify_pre_sweeping_heap), |
| verify_post_gc_heap_(verify_post_gc_heap), |
| verify_mod_union_table_(false), |
| verify_pre_gc_rosalloc_(verify_pre_gc_rosalloc), |
| verify_pre_sweeping_rosalloc_(verify_pre_sweeping_rosalloc), |
| verify_post_gc_rosalloc_(verify_post_gc_rosalloc), |
| last_gc_time_ns_(NanoTime()), |
| allocation_rate_(0), |
| /* For GC a lot mode, we limit the allocations stacks to be kGcAlotInterval allocations. This |
| * causes a lot of GC since we do a GC for alloc whenever the stack is full. When heap |
| * verification is enabled, we limit the size of allocation stacks to speed up their |
| * searching. |
| */ |
| max_allocation_stack_size_(kGCALotMode ? kGcAlotInterval |
| : (kVerifyObjectSupport > kVerifyObjectModeFast) ? KB : MB), |
| current_allocator_(kAllocatorTypeDlMalloc), |
| current_non_moving_allocator_(kAllocatorTypeNonMoving), |
| bump_pointer_space_(nullptr), |
| temp_space_(nullptr), |
| min_free_(min_free), |
| max_free_(max_free), |
| target_utilization_(target_utilization), |
| foreground_heap_growth_multiplier_(foreground_heap_growth_multiplier), |
| total_wait_time_(0), |
| total_allocation_time_(0), |
| verify_object_mode_(kVerifyObjectModeDisabled), |
| disable_moving_gc_count_(0), |
| running_on_valgrind_(Runtime::Current()->RunningOnValgrind()), |
| use_tlab_(use_tlab), |
| main_space_backup_(nullptr), |
| min_interval_homogeneous_space_compaction_by_oom_( |
| min_interval_homogeneous_space_compaction_by_oom), |
| last_time_homogeneous_space_compaction_by_oom_(NanoTime()), |
| use_homogeneous_space_compaction_for_oom_(use_homogeneous_space_compaction_for_oom) { |
| if (VLOG_IS_ON(heap) || VLOG_IS_ON(startup)) { |
| LOG(INFO) << "Heap() entering"; |
| } |
| // If we aren't the zygote, switch to the default non zygote allocator. This may update the |
| // entrypoints. |
| const bool is_zygote = Runtime::Current()->IsZygote(); |
| if (!is_zygote) { |
| // Background compaction is currently not supported for command line runs. |
| if (background_collector_type_ != foreground_collector_type_) { |
| VLOG(heap) << "Disabling background compaction for non zygote"; |
| background_collector_type_ = foreground_collector_type_; |
| } |
| } |
| ChangeCollector(desired_collector_type_); |
| live_bitmap_.reset(new accounting::HeapBitmap(this)); |
| mark_bitmap_.reset(new accounting::HeapBitmap(this)); |
| // Requested begin for the alloc space, to follow the mapped image and oat files |
| uint8_t* requested_alloc_space_begin = nullptr; |
| if (!image_file_name.empty()) { |
| std::string error_msg; |
| space::ImageSpace* image_space = space::ImageSpace::Create(image_file_name.c_str(), |
| image_instruction_set, |
| &error_msg); |
| if (image_space != nullptr) { |
| AddSpace(image_space); |
| // Oat files referenced by image files immediately follow them in memory, ensure alloc space |
| // isn't going to get in the middle |
| uint8_t* oat_file_end_addr = image_space->GetImageHeader().GetOatFileEnd(); |
| CHECK_GT(oat_file_end_addr, image_space->End()); |
| requested_alloc_space_begin = AlignUp(oat_file_end_addr, kPageSize); |
| } else { |
| LOG(WARNING) << "Could not create image space with image file '" << image_file_name << "'. " |
| << "Attempting to fall back to imageless running. Error was: " << error_msg; |
| } |
| } |
| /* |
| requested_alloc_space_begin -> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- |
| +- nonmoving space (non_moving_space_capacity)+- |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- |
| +-????????????????????????????????????????????+- |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- |
| +-main alloc space / bump space 1 (capacity_) +- |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- |
| +-????????????????????????????????????????????+- |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- |
| +-main alloc space2 / bump space 2 (capacity_)+- |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- |
| */ |
| bool support_homogeneous_space_compaction = |
| background_collector_type_ == gc::kCollectorTypeHomogeneousSpaceCompact || |
| use_homogeneous_space_compaction_for_oom; |
| // We may use the same space the main space for the non moving space if we don't need to compact |
| // from the main space. |
| // This is not the case if we support homogeneous compaction or have a moving background |
| // collector type. |
| bool separate_non_moving_space = is_zygote || |
| support_homogeneous_space_compaction || IsMovingGc(foreground_collector_type_) || |
| IsMovingGc(background_collector_type_); |
| if (foreground_collector_type == kCollectorTypeGSS) { |
| separate_non_moving_space = false; |
| } |
| std::unique_ptr<MemMap> main_mem_map_1; |
| std::unique_ptr<MemMap> main_mem_map_2; |
| uint8_t* request_begin = requested_alloc_space_begin; |
| if (request_begin != nullptr && separate_non_moving_space) { |
| request_begin += non_moving_space_capacity; |
| } |
| std::string error_str; |
| std::unique_ptr<MemMap> non_moving_space_mem_map; |
| if (separate_non_moving_space) { |
| // Reserve the non moving mem map before the other two since it needs to be at a specific |
| // address. |
| non_moving_space_mem_map.reset( |
| MemMap::MapAnonymous("non moving space", requested_alloc_space_begin, |
| non_moving_space_capacity, PROT_READ | PROT_WRITE, true, &error_str)); |
| CHECK(non_moving_space_mem_map != nullptr) << error_str; |
| // Try to reserve virtual memory at a lower address if we have a separate non moving space. |
| request_begin = reinterpret_cast<uint8_t*>(300 * MB); |
| } |
| // Attempt to create 2 mem maps at or after the requested begin. |
| main_mem_map_1.reset(MapAnonymousPreferredAddress(kMemMapSpaceName[0], request_begin, capacity_, |
| &error_str)); |
| CHECK(main_mem_map_1.get() != nullptr) << error_str; |
| if (support_homogeneous_space_compaction || |
| background_collector_type_ == kCollectorTypeSS || |
| foreground_collector_type_ == kCollectorTypeSS) { |
| main_mem_map_2.reset(MapAnonymousPreferredAddress(kMemMapSpaceName[1], main_mem_map_1->End(), |
| capacity_, &error_str)); |
| CHECK(main_mem_map_2.get() != nullptr) << error_str; |
| } |
| // Create the non moving space first so that bitmaps don't take up the address range. |
| if (separate_non_moving_space) { |
| // Non moving space is always dlmalloc since we currently don't have support for multiple |
| // active rosalloc spaces. |
| const size_t size = non_moving_space_mem_map->Size(); |
| non_moving_space_ = space::DlMallocSpace::CreateFromMemMap( |
| non_moving_space_mem_map.release(), "zygote / non moving space", kDefaultStartingSize, |
| initial_size, size, size, false); |
| non_moving_space_->SetFootprintLimit(non_moving_space_->Capacity()); |
| CHECK(non_moving_space_ != nullptr) << "Failed creating non moving space " |
| << requested_alloc_space_begin; |
| AddSpace(non_moving_space_); |
| } |
| // Create other spaces based on whether or not we have a moving GC. |
| if (IsMovingGc(foreground_collector_type_) && foreground_collector_type_ != kCollectorTypeGSS) { |
| // Create bump pointer spaces. |
| // We only to create the bump pointer if the foreground collector is a compacting GC. |
| // TODO: Place bump-pointer spaces somewhere to minimize size of card table. |
| bump_pointer_space_ = space::BumpPointerSpace::CreateFromMemMap("Bump pointer space 1", |
| main_mem_map_1.release()); |
| CHECK(bump_pointer_space_ != nullptr) << "Failed to create bump pointer space"; |
| AddSpace(bump_pointer_space_); |
| temp_space_ = space::BumpPointerSpace::CreateFromMemMap("Bump pointer space 2", |
| main_mem_map_2.release()); |
| CHECK(temp_space_ != nullptr) << "Failed to create bump pointer space"; |
| AddSpace(temp_space_); |
| CHECK(separate_non_moving_space); |
| } else { |
| CreateMainMallocSpace(main_mem_map_1.release(), initial_size, growth_limit_, capacity_); |
| CHECK(main_space_ != nullptr); |
| AddSpace(main_space_); |
| if (!separate_non_moving_space) { |
| non_moving_space_ = main_space_; |
| CHECK(!non_moving_space_->CanMoveObjects()); |
| } |
| if (foreground_collector_type_ == kCollectorTypeGSS) { |
| CHECK_EQ(foreground_collector_type_, background_collector_type_); |
| // Create bump pointer spaces instead of a backup space. |
| main_mem_map_2.release(); |
| bump_pointer_space_ = space::BumpPointerSpace::Create("Bump pointer space 1", |
| kGSSBumpPointerSpaceCapacity, nullptr); |
| CHECK(bump_pointer_space_ != nullptr); |
| AddSpace(bump_pointer_space_); |
| temp_space_ = space::BumpPointerSpace::Create("Bump pointer space 2", |
| kGSSBumpPointerSpaceCapacity, nullptr); |
| CHECK(temp_space_ != nullptr); |
| AddSpace(temp_space_); |
| } else if (main_mem_map_2.get() != nullptr) { |
| const char* name = kUseRosAlloc ? kRosAllocSpaceName[1] : kDlMallocSpaceName[1]; |
| main_space_backup_.reset(CreateMallocSpaceFromMemMap(main_mem_map_2.release(), initial_size, |
| growth_limit_, capacity_, name, true)); |
| CHECK(main_space_backup_.get() != nullptr); |
| // Add the space so its accounted for in the heap_begin and heap_end. |
| AddSpace(main_space_backup_.get()); |
| } |
| } |
| CHECK(non_moving_space_ != nullptr); |
| CHECK(!non_moving_space_->CanMoveObjects()); |
| // Allocate the large object space. |
| if (large_object_space_type == space::kLargeObjectSpaceTypeFreeList) { |
| large_object_space_ = space::FreeListSpace::Create("free list large object space", nullptr, |
| capacity_); |
| CHECK(large_object_space_ != nullptr) << "Failed to create large object space"; |
| } else if (large_object_space_type == space::kLargeObjectSpaceTypeMap) { |
| large_object_space_ = space::LargeObjectMapSpace::Create("mem map large object space"); |
| CHECK(large_object_space_ != nullptr) << "Failed to create large object space"; |
| } else { |
| // Disable the large object space by making the cutoff excessively large. |
| large_object_threshold_ = std::numeric_limits<size_t>::max(); |
| large_object_space_ = nullptr; |
| } |
| if (large_object_space_ != nullptr) { |
| AddSpace(large_object_space_); |
| } |
| // Compute heap capacity. Continuous spaces are sorted in order of Begin(). |
| CHECK(!continuous_spaces_.empty()); |
| // Relies on the spaces being sorted. |
| uint8_t* heap_begin = continuous_spaces_.front()->Begin(); |
| uint8_t* heap_end = continuous_spaces_.back()->Limit(); |
| size_t heap_capacity = heap_end - heap_begin; |
| // Remove the main backup space since it slows down the GC to have unused extra spaces. |
| if (main_space_backup_.get() != nullptr) { |
| RemoveSpace(main_space_backup_.get()); |
| } |
| // Allocate the card table. |
| card_table_.reset(accounting::CardTable::Create(heap_begin, heap_capacity)); |
| CHECK(card_table_.get() != NULL) << "Failed to create card table"; |
| // Card cache for now since it makes it easier for us to update the references to the copying |
| // spaces. |
| accounting::ModUnionTable* mod_union_table = |
| new accounting::ModUnionTableToZygoteAllocspace("Image mod-union table", this, |
| GetImageSpace()); |
| CHECK(mod_union_table != nullptr) << "Failed to create image mod-union table"; |
| AddModUnionTable(mod_union_table); |
| if (collector::SemiSpace::kUseRememberedSet && non_moving_space_ != main_space_) { |
| accounting::RememberedSet* non_moving_space_rem_set = |
| new accounting::RememberedSet("Non-moving space remembered set", this, non_moving_space_); |
| CHECK(non_moving_space_rem_set != nullptr) << "Failed to create non-moving space remembered set"; |
| AddRememberedSet(non_moving_space_rem_set); |
| } |
| // TODO: Count objects in the image space here? |
| num_bytes_allocated_.StoreRelaxed(0); |
| mark_stack_.reset(accounting::ObjectStack::Create("mark stack", kDefaultMarkStackSize, |
| kDefaultMarkStackSize)); |
| const size_t alloc_stack_capacity = max_allocation_stack_size_ + kAllocationStackReserveSize; |
| allocation_stack_.reset(accounting::ObjectStack::Create( |
| "allocation stack", max_allocation_stack_size_, alloc_stack_capacity)); |
| live_stack_.reset(accounting::ObjectStack::Create( |
| "live stack", max_allocation_stack_size_, alloc_stack_capacity)); |
| // It's still too early to take a lock because there are no threads yet, but we can create locks |
| // now. We don't create it earlier to make it clear that you can't use locks during heap |
| // initialization. |
| gc_complete_lock_ = new Mutex("GC complete lock"); |
| gc_complete_cond_.reset(new ConditionVariable("GC complete condition variable", |
| *gc_complete_lock_)); |
| heap_trim_request_lock_ = new Mutex("Heap trim request lock"); |
| last_gc_size_ = GetBytesAllocated(); |
| if (ignore_max_footprint_) { |
| SetIdealFootprint(std::numeric_limits<size_t>::max()); |
| concurrent_start_bytes_ = std::numeric_limits<size_t>::max(); |
| } |
| CHECK_NE(max_allowed_footprint_, 0U); |
| // Create our garbage collectors. |
| for (size_t i = 0; i < 2; ++i) { |
| const bool concurrent = i != 0; |
| garbage_collectors_.push_back(new collector::MarkSweep(this, concurrent)); |
| garbage_collectors_.push_back(new collector::PartialMarkSweep(this, concurrent)); |
| garbage_collectors_.push_back(new collector::StickyMarkSweep(this, concurrent)); |
| } |
| if (kMovingCollector) { |
| // TODO: Clean this up. |
| const bool generational = foreground_collector_type_ == kCollectorTypeGSS; |
| semi_space_collector_ = new collector::SemiSpace(this, generational, |
| generational ? "generational" : ""); |
| garbage_collectors_.push_back(semi_space_collector_); |
| concurrent_copying_collector_ = new collector::ConcurrentCopying(this); |
| garbage_collectors_.push_back(concurrent_copying_collector_); |
| mark_compact_collector_ = new collector::MarkCompact(this); |
| garbage_collectors_.push_back(mark_compact_collector_); |
| } |
| if (GetImageSpace() != nullptr && non_moving_space_ != nullptr && |
| (is_zygote || separate_non_moving_space || foreground_collector_type_ == kCollectorTypeGSS)) { |
| // Check that there's no gap between the image space and the non moving space so that the |
| // immune region won't break (eg. due to a large object allocated in the gap). This is only |
| // required when we're the zygote or using GSS. |
| bool no_gap = MemMap::CheckNoGaps(GetImageSpace()->GetMemMap(), |
| non_moving_space_->GetMemMap()); |
| if (!no_gap) { |
| MemMap::DumpMaps(LOG(ERROR)); |
| LOG(FATAL) << "There's a gap between the image space and the main space"; |
| } |
| } |
| if (running_on_valgrind_) { |
| Runtime::Current()->GetInstrumentation()->InstrumentQuickAllocEntryPoints(); |
| } |
| if (VLOG_IS_ON(heap) || VLOG_IS_ON(startup)) { |
| LOG(INFO) << "Heap() exiting"; |
| } |
| } |
| |
| MemMap* Heap::MapAnonymousPreferredAddress(const char* name, uint8_t* request_begin, |
| size_t capacity, std::string* out_error_str) { |
| while (true) { |
| MemMap* map = MemMap::MapAnonymous(name, request_begin, capacity, |
| PROT_READ | PROT_WRITE, true, out_error_str); |
| if (map != nullptr || request_begin == nullptr) { |
| return map; |
| } |
| // Retry a second time with no specified request begin. |
| request_begin = nullptr; |
| } |
| return nullptr; |
| } |
| |
| space::MallocSpace* Heap::CreateMallocSpaceFromMemMap(MemMap* mem_map, size_t initial_size, |
| size_t growth_limit, size_t capacity, |
| const char* name, bool can_move_objects) { |
| space::MallocSpace* malloc_space = nullptr; |
| if (kUseRosAlloc) { |
| // Create rosalloc space. |
| malloc_space = space::RosAllocSpace::CreateFromMemMap(mem_map, name, kDefaultStartingSize, |
| initial_size, growth_limit, capacity, |
| low_memory_mode_, can_move_objects); |
| } else { |
| malloc_space = space::DlMallocSpace::CreateFromMemMap(mem_map, name, kDefaultStartingSize, |
| initial_size, growth_limit, capacity, |
| can_move_objects); |
| } |
| if (collector::SemiSpace::kUseRememberedSet) { |
| accounting::RememberedSet* rem_set = |
| new accounting::RememberedSet(std::string(name) + " remembered set", this, malloc_space); |
| CHECK(rem_set != nullptr) << "Failed to create main space remembered set"; |
| AddRememberedSet(rem_set); |
| } |
| CHECK(malloc_space != nullptr) << "Failed to create " << name; |
| malloc_space->SetFootprintLimit(malloc_space->Capacity()); |
| return malloc_space; |
| } |
| |
| void Heap::CreateMainMallocSpace(MemMap* mem_map, size_t initial_size, size_t growth_limit, |
| size_t capacity) { |
| // Is background compaction is enabled? |
| bool can_move_objects = IsMovingGc(background_collector_type_) != |
| IsMovingGc(foreground_collector_type_) || use_homogeneous_space_compaction_for_oom_; |
| // If we are the zygote and don't yet have a zygote space, it means that the zygote fork will |
| // happen in the future. If this happens and we have kCompactZygote enabled we wish to compact |
| // from the main space to the zygote space. If background compaction is enabled, always pass in |
| // that we can move objets. |
| if (kCompactZygote && Runtime::Current()->IsZygote() && !can_move_objects) { |
| // After the zygote we want this to be false if we don't have background compaction enabled so |
| // that getting primitive array elements is faster. |
| // We never have homogeneous compaction with GSS and don't need a space with movable objects. |
| can_move_objects = !HasZygoteSpace() && foreground_collector_type_ != kCollectorTypeGSS; |
| } |
| if (collector::SemiSpace::kUseRememberedSet && main_space_ != nullptr) { |
| RemoveRememberedSet(main_space_); |
| } |
| const char* name = kUseRosAlloc ? kRosAllocSpaceName[0] : kDlMallocSpaceName[0]; |
| main_space_ = CreateMallocSpaceFromMemMap(mem_map, initial_size, growth_limit, capacity, name, |
| can_move_objects); |
| SetSpaceAsDefault(main_space_); |
| VLOG(heap) << "Created main space " << main_space_; |
| } |
| |
| void Heap::ChangeAllocator(AllocatorType allocator) { |
| if (current_allocator_ != allocator) { |
| // These two allocators are only used internally and don't have any entrypoints. |
| CHECK_NE(allocator, kAllocatorTypeLOS); |
| CHECK_NE(allocator, kAllocatorTypeNonMoving); |
| current_allocator_ = allocator; |
| MutexLock mu(nullptr, *Locks::runtime_shutdown_lock_); |
| SetQuickAllocEntryPointsAllocator(current_allocator_); |
| Runtime::Current()->GetInstrumentation()->ResetQuickAllocEntryPoints(); |
| } |
| } |
| |
| void Heap::DisableMovingGc() { |
| if (IsMovingGc(foreground_collector_type_)) { |
| foreground_collector_type_ = kCollectorTypeCMS; |
| } |
| if (IsMovingGc(background_collector_type_)) { |
| background_collector_type_ = foreground_collector_type_; |
| } |
| TransitionCollector(foreground_collector_type_); |
| ThreadList* tl = Runtime::Current()->GetThreadList(); |
| Thread* self = Thread::Current(); |
| ScopedThreadStateChange tsc(self, kSuspended); |
| tl->SuspendAll(); |
| // Something may have caused the transition to fail. |
| if (!IsMovingGc(collector_type_) && non_moving_space_ != main_space_) { |
| CHECK(main_space_ != nullptr); |
| // The allocation stack may have non movable objects in it. We need to flush it since the GC |
| // can't only handle marking allocation stack objects of one non moving space and one main |
| // space. |
| { |
| WriterMutexLock mu(self, *Locks::heap_bitmap_lock_); |
| FlushAllocStack(); |
| } |
| main_space_->DisableMovingObjects(); |
| non_moving_space_ = main_space_; |
| CHECK(!non_moving_space_->CanMoveObjects()); |
| } |
| tl->ResumeAll(); |
| } |
| |
| std::string Heap::SafeGetClassDescriptor(mirror::Class* klass) { |
| if (!IsValidContinuousSpaceObjectAddress(klass)) { |
| return StringPrintf("<non heap address klass %p>", klass); |
| } |
| mirror::Class* component_type = klass->GetComponentType<kVerifyNone>(); |
| if (IsValidContinuousSpaceObjectAddress(component_type) && klass->IsArrayClass<kVerifyNone>()) { |
| std::string result("["); |
| result += SafeGetClassDescriptor(component_type); |
| return result; |
| } else if (UNLIKELY(klass->IsPrimitive<kVerifyNone>())) { |
| return Primitive::Descriptor(klass->GetPrimitiveType<kVerifyNone>()); |
| } else if (UNLIKELY(klass->IsProxyClass<kVerifyNone>())) { |
| return Runtime::Current()->GetClassLinker()->GetDescriptorForProxy(klass); |
| } else { |
| mirror::DexCache* dex_cache = klass->GetDexCache<kVerifyNone>(); |
| if (!IsValidContinuousSpaceObjectAddress(dex_cache)) { |
| return StringPrintf("<non heap address dex_cache %p>", dex_cache); |
| } |
| const DexFile* dex_file = dex_cache->GetDexFile(); |
| uint16_t class_def_idx = klass->GetDexClassDefIndex(); |
| if (class_def_idx == DexFile::kDexNoIndex16) { |
| return "<class def not found>"; |
| } |
| const DexFile::ClassDef& class_def = dex_file->GetClassDef(class_def_idx); |
| const DexFile::TypeId& type_id = dex_file->GetTypeId(class_def.class_idx_); |
| return dex_file->GetTypeDescriptor(type_id); |
| } |
| } |
| |
| std::string Heap::SafePrettyTypeOf(mirror::Object* obj) { |
| if (obj == nullptr) { |
| return "null"; |
| } |
| mirror::Class* klass = obj->GetClass<kVerifyNone>(); |
| if (klass == nullptr) { |
| return "(class=null)"; |
| } |
| std::string result(SafeGetClassDescriptor(klass)); |
| if (obj->IsClass()) { |
| result += "<" + SafeGetClassDescriptor(obj->AsClass<kVerifyNone>()) + ">"; |
| } |
| return result; |
| } |
| |
| void Heap::DumpObject(std::ostream& stream, mirror::Object* obj) { |
| if (obj == nullptr) { |
| stream << "(obj=null)"; |
| return; |
| } |
| if (IsAligned<kObjectAlignment>(obj)) { |
| space::Space* space = nullptr; |
| // Don't use find space since it only finds spaces which actually contain objects instead of |
| // spaces which may contain objects (e.g. cleared bump pointer spaces). |
| for (const auto& cur_space : continuous_spaces_) { |
| if (cur_space->HasAddress(obj)) { |
| space = cur_space; |
| break; |
| } |
| } |
| // Unprotect all the spaces. |
| for (const auto& space : continuous_spaces_) { |
| mprotect(space->Begin(), space->Capacity(), PROT_READ | PROT_WRITE); |
| } |
| stream << "Object " << obj; |
| if (space != nullptr) { |
| stream << " in space " << *space; |
| } |
| mirror::Class* klass = obj->GetClass<kVerifyNone>(); |
| stream << "\nclass=" << klass; |
| if (klass != nullptr) { |
| stream << " type= " << SafePrettyTypeOf(obj); |
| } |
| // Re-protect the address we faulted on. |
| mprotect(AlignDown(obj, kPageSize), kPageSize, PROT_NONE); |
| } |
| } |
| |
| bool Heap::IsCompilingBoot() const { |
| if (!Runtime::Current()->IsCompiler()) { |
| return false; |
| } |
| for (const auto& space : continuous_spaces_) { |
| if (space->IsImageSpace() || space->IsZygoteSpace()) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| bool Heap::HasImageSpace() const { |
| for (const auto& space : continuous_spaces_) { |
| if (space->IsImageSpace()) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| void Heap::IncrementDisableMovingGC(Thread* self) { |
| // Need to do this holding the lock to prevent races where the GC is about to run / running when |
| // we attempt to disable it. |
| ScopedThreadStateChange tsc(self, kWaitingForGcToComplete); |
| MutexLock mu(self, *gc_complete_lock_); |
| ++disable_moving_gc_count_; |
| if (IsMovingGc(collector_type_running_)) { |
| WaitForGcToCompleteLocked(kGcCauseDisableMovingGc, self); |
| } |
| } |
| |
| void Heap::DecrementDisableMovingGC(Thread* self) { |
| MutexLock mu(self, *gc_complete_lock_); |
| CHECK_GE(disable_moving_gc_count_, 0U); |
| --disable_moving_gc_count_; |
| } |
| |
| void Heap::UpdateProcessState(ProcessState process_state) { |
| if (process_state_ != process_state) { |
| process_state_ = process_state; |
| for (size_t i = 1; i <= kCollectorTransitionStressIterations; ++i) { |
| // Start at index 1 to avoid "is always false" warning. |
| // Have iteration 1 always transition the collector. |
| TransitionCollector((((i & 1) == 1) == (process_state_ == kProcessStateJankPerceptible)) |
| ? foreground_collector_type_ : background_collector_type_); |
| usleep(kCollectorTransitionStressWait); |
| } |
| if (process_state_ == kProcessStateJankPerceptible) { |
| // Transition back to foreground right away to prevent jank. |
| RequestCollectorTransition(foreground_collector_type_, 0); |
| } else { |
| // Don't delay for debug builds since we may want to stress test the GC. |
| // If background_collector_type_ is kCollectorTypeHomogeneousSpaceCompact then we have |
| // special handling which does a homogenous space compaction once but then doesn't transition |
| // the collector. |
| RequestCollectorTransition(background_collector_type_, |
| kIsDebugBuild ? 0 : kCollectorTransitionWait); |
| } |
| } |
| } |
| |
| void Heap::CreateThreadPool() { |
| const size_t num_threads = std::max(parallel_gc_threads_, conc_gc_threads_); |
| if (num_threads != 0) { |
| thread_pool_.reset(new ThreadPool("Heap thread pool", num_threads)); |
| } |
| } |
| |
| void Heap::VisitObjects(ObjectCallback callback, void* arg) { |
| // GCs can move objects, so don't allow this. |
| ScopedAssertNoThreadSuspension ants(Thread::Current(), "Visiting objects"); |
| if (bump_pointer_space_ != nullptr) { |
| // Visit objects in bump pointer space. |
| bump_pointer_space_->Walk(callback, arg); |
| } |
| // TODO: Switch to standard begin and end to use ranged a based loop. |
| for (mirror::Object** it = allocation_stack_->Begin(), **end = allocation_stack_->End(); |
| it < end; ++it) { |
| mirror::Object* obj = *it; |
| if (obj != nullptr && obj->GetClass() != nullptr) { |
| // Avoid the race condition caused by the object not yet being written into the allocation |
| // stack or the class not yet being written in the object. Or, if kUseThreadLocalAllocationStack, |
| // there can be nulls on the allocation stack. |
| callback(obj, arg); |
| } |
| } |
| GetLiveBitmap()->Walk(callback, arg); |
| } |
| |
| void Heap::MarkAllocStackAsLive(accounting::ObjectStack* stack) { |
| space::ContinuousSpace* space1 = main_space_ != nullptr ? main_space_ : non_moving_space_; |
| space::ContinuousSpace* space2 = non_moving_space_; |
| // TODO: Generalize this to n bitmaps? |
| CHECK(space1 != nullptr); |
| CHECK(space2 != nullptr); |
| MarkAllocStack(space1->GetLiveBitmap(), space2->GetLiveBitmap(), |
| (large_object_space_ != nullptr ? large_object_space_->GetLiveBitmap() : nullptr), |
| stack); |
| } |
| |
| void Heap::DeleteThreadPool() { |
| thread_pool_.reset(nullptr); |
| } |
| |
| void Heap::AddSpace(space::Space* space) { |
| CHECK(space != nullptr); |
| WriterMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); |
| if (space->IsContinuousSpace()) { |
| DCHECK(!space->IsDiscontinuousSpace()); |
| space::ContinuousSpace* continuous_space = space->AsContinuousSpace(); |
| // Continuous spaces don't necessarily have bitmaps. |
| accounting::ContinuousSpaceBitmap* live_bitmap = continuous_space->GetLiveBitmap(); |
| accounting::ContinuousSpaceBitmap* mark_bitmap = continuous_space->GetMarkBitmap(); |
| if (live_bitmap != nullptr) { |
| CHECK(mark_bitmap != nullptr); |
| live_bitmap_->AddContinuousSpaceBitmap(live_bitmap); |
| mark_bitmap_->AddContinuousSpaceBitmap(mark_bitmap); |
| } |
| continuous_spaces_.push_back(continuous_space); |
| // Ensure that spaces remain sorted in increasing order of start address. |
| std::sort(continuous_spaces_.begin(), continuous_spaces_.end(), |
| [](const space::ContinuousSpace* a, const space::ContinuousSpace* b) { |
| return a->Begin() < b->Begin(); |
| }); |
| } else { |
| CHECK(space->IsDiscontinuousSpace()); |
| space::DiscontinuousSpace* discontinuous_space = space->AsDiscontinuousSpace(); |
| live_bitmap_->AddLargeObjectBitmap(discontinuous_space->GetLiveBitmap()); |
| mark_bitmap_->AddLargeObjectBitmap(discontinuous_space->GetMarkBitmap()); |
| discontinuous_spaces_.push_back(discontinuous_space); |
| } |
| if (space->IsAllocSpace()) { |
| alloc_spaces_.push_back(space->AsAllocSpace()); |
| } |
| } |
| |
| void Heap::SetSpaceAsDefault(space::ContinuousSpace* continuous_space) { |
| WriterMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); |
| if (continuous_space->IsDlMallocSpace()) { |
| dlmalloc_space_ = continuous_space->AsDlMallocSpace(); |
| } else if (continuous_space->IsRosAllocSpace()) { |
| rosalloc_space_ = continuous_space->AsRosAllocSpace(); |
| } |
| } |
| |
| void Heap::RemoveSpace(space::Space* space) { |
| DCHECK(space != nullptr); |
| WriterMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); |
| if (space->IsContinuousSpace()) { |
| DCHECK(!space->IsDiscontinuousSpace()); |
| space::ContinuousSpace* continuous_space = space->AsContinuousSpace(); |
| // Continuous spaces don't necessarily have bitmaps. |
| accounting::ContinuousSpaceBitmap* live_bitmap = continuous_space->GetLiveBitmap(); |
| accounting::ContinuousSpaceBitmap* mark_bitmap = continuous_space->GetMarkBitmap(); |
| if (live_bitmap != nullptr) { |
| DCHECK(mark_bitmap != nullptr); |
| live_bitmap_->RemoveContinuousSpaceBitmap(live_bitmap); |
| mark_bitmap_->RemoveContinuousSpaceBitmap(mark_bitmap); |
| } |
| auto it = std::find(continuous_spaces_.begin(), continuous_spaces_.end(), continuous_space); |
| DCHECK(it != continuous_spaces_.end()); |
| continuous_spaces_.erase(it); |
| } else { |
| DCHECK(space->IsDiscontinuousSpace()); |
| space::DiscontinuousSpace* discontinuous_space = space->AsDiscontinuousSpace(); |
| live_bitmap_->RemoveLargeObjectBitmap(discontinuous_space->GetLiveBitmap()); |
| mark_bitmap_->RemoveLargeObjectBitmap(discontinuous_space->GetMarkBitmap()); |
| auto it = std::find(discontinuous_spaces_.begin(), discontinuous_spaces_.end(), |
| discontinuous_space); |
| DCHECK(it != discontinuous_spaces_.end()); |
| discontinuous_spaces_.erase(it); |
| } |
| if (space->IsAllocSpace()) { |
| auto it = std::find(alloc_spaces_.begin(), alloc_spaces_.end(), space->AsAllocSpace()); |
| DCHECK(it != alloc_spaces_.end()); |
| alloc_spaces_.erase(it); |
| } |
| } |
| |
| void Heap::DumpGcPerformanceInfo(std::ostream& os) { |
| // Dump cumulative timings. |
| os << "Dumping cumulative Gc timings\n"; |
| uint64_t total_duration = 0; |
| // Dump cumulative loggers for each GC type. |
| uint64_t total_paused_time = 0; |
| for (auto& collector : garbage_collectors_) { |
| total_duration += collector->GetCumulativeTimings().GetTotalNs(); |
| total_paused_time += collector->GetTotalPausedTimeNs(); |
| collector->DumpPerformanceInfo(os); |
| collector->ResetMeasurements(); |
| } |
| uint64_t allocation_time = |
| static_cast<uint64_t>(total_allocation_time_.LoadRelaxed()) * kTimeAdjust; |
| if (total_duration != 0) { |
| const double total_seconds = static_cast<double>(total_duration / 1000) / 1000000.0; |
| os << "Total time spent in GC: " << PrettyDuration(total_duration) << "\n"; |
| os << "Mean GC size throughput: " |
| << PrettySize(GetBytesFreedEver() / total_seconds) << "/s\n"; |
| os << "Mean GC object throughput: " |
| << (GetObjectsFreedEver() / total_seconds) << " objects/s\n"; |
| } |
| uint64_t total_objects_allocated = GetObjectsAllocatedEver(); |
| os << "Total number of allocations " << total_objects_allocated << "\n"; |
| uint64_t total_bytes_allocated = GetBytesAllocatedEver(); |
| os << "Total bytes allocated " << PrettySize(total_bytes_allocated) << "\n"; |
| os << "Free memory " << PrettySize(GetFreeMemory()) << "\n"; |
| os << "Free memory until GC " << PrettySize(GetFreeMemoryUntilGC()) << "\n"; |
| os << "Free memory until OOME " << PrettySize(GetFreeMemoryUntilOOME()) << "\n"; |
| os << "Total memory " << PrettySize(GetTotalMemory()) << "\n"; |
| os << "Max memory " << PrettySize(GetMaxMemory()) << "\n"; |
| if (kMeasureAllocationTime) { |
| os << "Total time spent allocating: " << PrettyDuration(allocation_time) << "\n"; |
| os << "Mean allocation time: " << PrettyDuration(allocation_time / total_objects_allocated) |
| << "\n"; |
| } |
| if (HasZygoteSpace()) { |
| os << "Zygote space size " << PrettySize(zygote_space_->Size()) << "\n"; |
| } |
| os << "Total mutator paused time: " << PrettyDuration(total_paused_time) << "\n"; |
| os << "Total time waiting for GC to complete: " << PrettyDuration(total_wait_time_) << "\n"; |
| BaseMutex::DumpAll(os); |
| } |
| |
| Heap::~Heap() { |
| VLOG(heap) << "Starting ~Heap()"; |
| STLDeleteElements(&garbage_collectors_); |
| // If we don't reset then the mark stack complains in its destructor. |
| allocation_stack_->Reset(); |
| live_stack_->Reset(); |
| STLDeleteValues(&mod_union_tables_); |
| STLDeleteValues(&remembered_sets_); |
| STLDeleteElements(&continuous_spaces_); |
| STLDeleteElements(&discontinuous_spaces_); |
| delete gc_complete_lock_; |
| delete heap_trim_request_lock_; |
| VLOG(heap) << "Finished ~Heap()"; |
| } |
| |
| space::ContinuousSpace* Heap::FindContinuousSpaceFromObject(const mirror::Object* obj, |
| bool fail_ok) const { |
| for (const auto& space : continuous_spaces_) { |
| if (space->Contains(obj)) { |
| return space; |
| } |
| } |
| if (!fail_ok) { |
| LOG(FATAL) << "object " << reinterpret_cast<const void*>(obj) << " not inside any spaces!"; |
| } |
| return NULL; |
| } |
| |
| space::DiscontinuousSpace* Heap::FindDiscontinuousSpaceFromObject(const mirror::Object* obj, |
| bool fail_ok) const { |
| for (const auto& space : discontinuous_spaces_) { |
| if (space->Contains(obj)) { |
| return space; |
| } |
| } |
| if (!fail_ok) { |
| LOG(FATAL) << "object " << reinterpret_cast<const void*>(obj) << " not inside any spaces!"; |
| } |
| return NULL; |
| } |
| |
| space::Space* Heap::FindSpaceFromObject(const mirror::Object* obj, bool fail_ok) const { |
| space::Space* result = FindContinuousSpaceFromObject(obj, true); |
| if (result != NULL) { |
| return result; |
| } |
| return FindDiscontinuousSpaceFromObject(obj, fail_ok); |
| } |
| |
| space::ImageSpace* Heap::GetImageSpace() const { |
| for (const auto& space : continuous_spaces_) { |
| if (space->IsImageSpace()) { |
| return space->AsImageSpace(); |
| } |
| } |
| return NULL; |
| } |
| |
| void Heap::ThrowOutOfMemoryError(Thread* self, size_t byte_count, AllocatorType allocator_type) { |
| std::ostringstream oss; |
| size_t total_bytes_free = GetFreeMemory(); |
| oss << "Failed to allocate a " << byte_count << " byte allocation with " << total_bytes_free |
| << " free bytes and " << PrettySize(GetFreeMemoryUntilOOME()) << " until OOM"; |
| // If the allocation failed due to fragmentation, print out the largest continuous allocation. |
| if (total_bytes_free >= byte_count) { |
| space::AllocSpace* space = nullptr; |
| if (allocator_type == kAllocatorTypeNonMoving) { |
| space = non_moving_space_; |
| } else if (allocator_type == kAllocatorTypeRosAlloc || |
| allocator_type == kAllocatorTypeDlMalloc) { |
| space = main_space_; |
| } else if (allocator_type == kAllocatorTypeBumpPointer || |
| allocator_type == kAllocatorTypeTLAB) { |
| space = bump_pointer_space_; |
| } |
| if (space != nullptr) { |
| space->LogFragmentationAllocFailure(oss, byte_count); |
| } |
| } |
| self->ThrowOutOfMemoryError(oss.str().c_str()); |
| } |
| |
| void Heap::DoPendingTransitionOrTrim() { |
| Thread* self = Thread::Current(); |
| CollectorType desired_collector_type; |
| // Wait until we reach the desired transition time. |
| while (true) { |
| uint64_t wait_time; |
| { |
| MutexLock mu(self, *heap_trim_request_lock_); |
| desired_collector_type = desired_collector_type_; |
| uint64_t current_time = NanoTime(); |
| if (current_time >= heap_transition_or_trim_target_time_) { |
| break; |
| } |
| wait_time = heap_transition_or_trim_target_time_ - current_time; |
| } |
| ScopedThreadStateChange tsc(self, kSleeping); |
| usleep(wait_time / 1000); // Usleep takes microseconds. |
| } |
| // Launch homogeneous space compaction if it is desired. |
| if (desired_collector_type == kCollectorTypeHomogeneousSpaceCompact) { |
| if (!CareAboutPauseTimes()) { |
| PerformHomogeneousSpaceCompact(); |
| } |
| // No need to Trim(). Homogeneous space compaction may free more virtual and physical memory. |
| desired_collector_type = collector_type_; |
| return; |
| } |
| // Transition the collector if the desired collector type is not the same as the current |
| // collector type. |
| TransitionCollector(desired_collector_type); |
| if (!CareAboutPauseTimes()) { |
| // Deflate the monitors, this can cause a pause but shouldn't matter since we don't care |
| // about pauses. |
| Runtime* runtime = Runtime::Current(); |
| runtime->GetThreadList()->SuspendAll(); |
| uint64_t start_time = NanoTime(); |
| size_t count = runtime->GetMonitorList()->DeflateMonitors(); |
| VLOG(heap) << "Deflating " << count << " monitors took " |
| << PrettyDuration(NanoTime() - start_time); |
| runtime->GetThreadList()->ResumeAll(); |
| } |
| // Do a heap trim if it is needed. |
| Trim(); |
| } |
| |
| void Heap::Trim() { |
| Thread* self = Thread::Current(); |
| { |
| MutexLock mu(self, *heap_trim_request_lock_); |
| if (!heap_trim_request_pending_ || last_trim_time_ + kHeapTrimWait >= NanoTime()) { |
| return; |
| } |
| last_trim_time_ = NanoTime(); |
| heap_trim_request_pending_ = false; |
| } |
| { |
| // Need to do this before acquiring the locks since we don't want to get suspended while |
| // holding any locks. |
| ScopedThreadStateChange tsc(self, kWaitingForGcToComplete); |
| // Pretend we are doing a GC to prevent background compaction from deleting the space we are |
| // trimming. |
| MutexLock mu(self, *gc_complete_lock_); |
| // Ensure there is only one GC at a time. |
| WaitForGcToCompleteLocked(kGcCauseTrim, self); |
| collector_type_running_ = kCollectorTypeHeapTrim; |
| } |
| uint64_t start_ns = NanoTime(); |
| // Trim the managed spaces. |
| uint64_t total_alloc_space_allocated = 0; |
| uint64_t total_alloc_space_size = 0; |
| uint64_t managed_reclaimed = 0; |
| for (const auto& space : continuous_spaces_) { |
| if (space->IsMallocSpace()) { |
| gc::space::MallocSpace* malloc_space = space->AsMallocSpace(); |
| if (malloc_space->IsRosAllocSpace() || !CareAboutPauseTimes()) { |
| // Don't trim dlmalloc spaces if we care about pauses since this can hold the space lock |
| // for a long period of time. |
| managed_reclaimed += malloc_space->Trim(); |
| } |
| total_alloc_space_size += malloc_space->Size(); |
| } |
| } |
| total_alloc_space_allocated = GetBytesAllocated(); |
| if (large_object_space_ != nullptr) { |
| total_alloc_space_allocated -= large_object_space_->GetBytesAllocated(); |
| } |
| if (bump_pointer_space_ != nullptr) { |
| total_alloc_space_allocated -= bump_pointer_space_->Size(); |
| } |
| const float managed_utilization = static_cast<float>(total_alloc_space_allocated) / |
| static_cast<float>(total_alloc_space_size); |
| uint64_t gc_heap_end_ns = NanoTime(); |
| // We never move things in the native heap, so we can finish the GC at this point. |
| FinishGC(self, collector::kGcTypeNone); |
| size_t native_reclaimed = 0; |
| |
| #ifdef HAVE_ANDROID_OS |
| // Only trim the native heap if we don't care about pauses. |
| if (!CareAboutPauseTimes()) { |
| #if defined(USE_DLMALLOC) |
| // Trim the native heap. |
| dlmalloc_trim(0); |
| dlmalloc_inspect_all(DlmallocMadviseCallback, &native_reclaimed); |
| #elif defined(USE_JEMALLOC) |
| // Jemalloc does it's own internal trimming. |
| #else |
| UNIMPLEMENTED(WARNING) << "Add trimming support"; |
| #endif |
| } |
| #endif // HAVE_ANDROID_OS |
| uint64_t end_ns = NanoTime(); |
| VLOG(heap) << "Heap trim of managed (duration=" << PrettyDuration(gc_heap_end_ns - start_ns) |
| << ", advised=" << PrettySize(managed_reclaimed) << ") and native (duration=" |
| << PrettyDuration(end_ns - gc_heap_end_ns) << ", advised=" << PrettySize(native_reclaimed) |
| << ") heaps. Managed heap utilization of " << static_cast<int>(100 * managed_utilization) |
| << "%."; |
| } |
| |
| bool Heap::IsValidObjectAddress(const mirror::Object* obj) const { |
| // Note: we deliberately don't take the lock here, and mustn't test anything that would require |
| // taking the lock. |
| if (obj == nullptr) { |
| return true; |
| } |
| return IsAligned<kObjectAlignment>(obj) && FindSpaceFromObject(obj, true) != nullptr; |
| } |
| |
| bool Heap::IsNonDiscontinuousSpaceHeapAddress(const mirror::Object* obj) const { |
| return FindContinuousSpaceFromObject(obj, true) != nullptr; |
| } |
| |
| bool Heap::IsValidContinuousSpaceObjectAddress(const mirror::Object* obj) const { |
| if (obj == nullptr || !IsAligned<kObjectAlignment>(obj)) { |
| return false; |
| } |
| for (const auto& space : continuous_spaces_) { |
| if (space->HasAddress(obj)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool Heap::IsLiveObjectLocked(mirror::Object* obj, bool search_allocation_stack, |
| bool search_live_stack, bool sorted) { |
| if (UNLIKELY(!IsAligned<kObjectAlignment>(obj))) { |
| return false; |
| } |
| if (bump_pointer_space_ != nullptr && bump_pointer_space_->HasAddress(obj)) { |
| mirror::Class* klass = obj->GetClass<kVerifyNone>(); |
| if (obj == klass) { |
| // This case happens for java.lang.Class. |
| return true; |
| } |
| return VerifyClassClass(klass) && IsLiveObjectLocked(klass); |
| } else if (temp_space_ != nullptr && temp_space_->HasAddress(obj)) { |
| // If we are in the allocated region of the temp space, then we are probably live (e.g. during |
| // a GC). When a GC isn't running End() - Begin() is 0 which means no objects are contained. |
| return temp_space_->Contains(obj); |
| } |
| space::ContinuousSpace* c_space = FindContinuousSpaceFromObject(obj, true); |
| space::DiscontinuousSpace* d_space = nullptr; |
| if (c_space != nullptr) { |
| if (c_space->GetLiveBitmap()->Test(obj)) { |
| return true; |
| } |
| } else { |
| d_space = FindDiscontinuousSpaceFromObject(obj, true); |
| if (d_space != nullptr) { |
| if (d_space->GetLiveBitmap()->Test(obj)) { |
| return true; |
| } |
| } |
| } |
| // This is covering the allocation/live stack swapping that is done without mutators suspended. |
| for (size_t i = 0; i < (sorted ? 1 : 5); ++i) { |
| if (i > 0) { |
| NanoSleep(MsToNs(10)); |
| } |
| if (search_allocation_stack) { |
| if (sorted) { |
| if (allocation_stack_->ContainsSorted(obj)) { |
| return true; |
| } |
| } else if (allocation_stack_->Contains(obj)) { |
| return true; |
| } |
| } |
| |
| if (search_live_stack) { |
| if (sorted) { |
| if (live_stack_->ContainsSorted(obj)) { |
| return true; |
| } |
| } else if (live_stack_->Contains(obj)) { |
| return true; |
| } |
| } |
| } |
| // We need to check the bitmaps again since there is a race where we mark something as live and |
| // then clear the stack containing it. |
| if (c_space != nullptr) { |
| if (c_space->GetLiveBitmap()->Test(obj)) { |
| return true; |
| } |
| } else { |
| d_space = FindDiscontinuousSpaceFromObject(obj, true); |
| if (d_space != nullptr && d_space->GetLiveBitmap()->Test(obj)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| std::string Heap::DumpSpaces() const { |
| std::ostringstream oss; |
| DumpSpaces(oss); |
| return oss.str(); |
| } |
| |
| void Heap::DumpSpaces(std::ostream& stream) const { |
| for (const auto& space : continuous_spaces_) { |
| accounting::ContinuousSpaceBitmap* live_bitmap = space->GetLiveBitmap(); |
| accounting::ContinuousSpaceBitmap* mark_bitmap = space->GetMarkBitmap(); |
| stream << space << " " << *space << "\n"; |
| if (live_bitmap != nullptr) { |
| stream << live_bitmap << " " << *live_bitmap << "\n"; |
| } |
| if (mark_bitmap != nullptr) { |
| stream << mark_bitmap << " " << *mark_bitmap << "\n"; |
| } |
| } |
| for (const auto& space : discontinuous_spaces_) { |
| stream << space << " " << *space << "\n"; |
| } |
| } |
| |
| void Heap::VerifyObjectBody(mirror::Object* obj) { |
| if (verify_object_mode_ == kVerifyObjectModeDisabled) { |
| return; |
| } |
| |
| // Ignore early dawn of the universe verifications. |
| if (UNLIKELY(static_cast<size_t>(num_bytes_allocated_.LoadRelaxed()) < 10 * KB)) { |
| return; |
| } |
| CHECK(IsAligned<kObjectAlignment>(obj)) << "Object isn't aligned: " << obj; |
| mirror::Class* c = obj->GetFieldObject<mirror::Class, kVerifyNone>(mirror::Object::ClassOffset()); |
| CHECK(c != nullptr) << "Null class in object " << obj; |
| CHECK(IsAligned<kObjectAlignment>(c)) << "Class " << c << " not aligned in object " << obj; |
| CHECK(VerifyClassClass(c)); |
| |
| if (verify_object_mode_ > kVerifyObjectModeFast) { |
| // Note: the bitmap tests below are racy since we don't hold the heap bitmap lock. |
| CHECK(IsLiveObjectLocked(obj)) << "Object is dead " << obj << "\n" << DumpSpaces(); |
| } |
| } |
| |
| void Heap::VerificationCallback(mirror::Object* obj, void* arg) { |
| reinterpret_cast<Heap*>(arg)->VerifyObjectBody(obj); |
| } |
| |
| void Heap::VerifyHeap() { |
| ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); |
| GetLiveBitmap()->Walk(Heap::VerificationCallback, this); |
| } |
| |
| void Heap::RecordFree(uint64_t freed_objects, int64_t freed_bytes) { |
| // Use signed comparison since freed bytes can be negative when background compaction foreground |
| // transitions occurs. This is caused by the moving objects from a bump pointer space to a |
| // free list backed space typically increasing memory footprint due to padding and binning. |
| DCHECK_LE(freed_bytes, static_cast<int64_t>(num_bytes_allocated_.LoadRelaxed())); |
| // Note: This relies on 2s complement for handling negative freed_bytes. |
| num_bytes_allocated_.FetchAndSubSequentiallyConsistent(static_cast<ssize_t>(freed_bytes)); |
| if (Runtime::Current()->HasStatsEnabled()) { |
| RuntimeStats* thread_stats = Thread::Current()->GetStats(); |
| thread_stats->freed_objects += freed_objects; |
| thread_stats->freed_bytes += freed_bytes; |
| // TODO: Do this concurrently. |
| RuntimeStats* global_stats = Runtime::Current()->GetStats(); |
| global_stats->freed_objects += freed_objects; |
| global_stats->freed_bytes += freed_bytes; |
| } |
| } |
| |
| space::RosAllocSpace* Heap::GetRosAllocSpace(gc::allocator::RosAlloc* rosalloc) const { |
| for (const auto& space : continuous_spaces_) { |
| if (space->AsContinuousSpace()->IsRosAllocSpace()) { |
| if (space->AsContinuousSpace()->AsRosAllocSpace()->GetRosAlloc() == rosalloc) { |
| return space->AsContinuousSpace()->AsRosAllocSpace(); |
| } |
| } |
| } |
| return nullptr; |
| } |
| |
| mirror::Object* Heap::AllocateInternalWithGc(Thread* self, AllocatorType allocator, |
| size_t alloc_size, size_t* bytes_allocated, |
| size_t* usable_size, |
| mirror::Class** klass) { |
| bool was_default_allocator = allocator == GetCurrentAllocator(); |
| // Make sure there is no pending exception since we may need to throw an OOME. |
| self->AssertNoPendingException(); |
| DCHECK(klass != nullptr); |
| StackHandleScope<1> hs(self); |
| HandleWrapper<mirror::Class> h(hs.NewHandleWrapper(klass)); |
| klass = nullptr; // Invalidate for safety. |
| // The allocation failed. If the GC is running, block until it completes, and then retry the |
| // allocation. |
| collector::GcType last_gc = WaitForGcToComplete(kGcCauseForAlloc, self); |
| if (last_gc != collector::kGcTypeNone) { |
| // If we were the default allocator but the allocator changed while we were suspended, |
| // abort the allocation. |
| if (was_default_allocator && allocator != GetCurrentAllocator()) { |
| return nullptr; |
| } |
| // A GC was in progress and we blocked, retry allocation now that memory has been freed. |
| mirror::Object* ptr = TryToAllocate<true, false>(self, allocator, alloc_size, bytes_allocated, |
| usable_size); |
| if (ptr != nullptr) { |
| return ptr; |
| } |
| } |
| |
| collector::GcType tried_type = next_gc_type_; |
| const bool gc_ran = |
| CollectGarbageInternal(tried_type, kGcCauseForAlloc, false) != collector::kGcTypeNone; |
| if (was_default_allocator && allocator != GetCurrentAllocator()) { |
| return nullptr; |
| } |
| if (gc_ran) { |
| mirror::Object* ptr = TryToAllocate<true, false>(self, allocator, alloc_size, bytes_allocated, |
| usable_size); |
| if (ptr != nullptr) { |
| return ptr; |
| } |
| } |
| |
| // Loop through our different Gc types and try to Gc until we get enough free memory. |
| for (collector::GcType gc_type : gc_plan_) { |
| if (gc_type == tried_type) { |
| continue; |
| } |
| // Attempt to run the collector, if we succeed, re-try the allocation. |
| const bool gc_ran = |
| CollectGarbageInternal(gc_type, kGcCauseForAlloc, false) != collector::kGcTypeNone; |
| if (was_default_allocator && allocator != GetCurrentAllocator()) { |
| return nullptr; |
| } |
| if (gc_ran) { |
| // Did we free sufficient memory for the allocation to succeed? |
| mirror::Object* ptr = TryToAllocate<true, false>(self, allocator, alloc_size, bytes_allocated, |
| usable_size); |
| if (ptr != nullptr) { |
| return ptr; |
| } |
| } |
| } |
| // Allocations have failed after GCs; this is an exceptional state. |
| // Try harder, growing the heap if necessary. |
| mirror::Object* ptr = TryToAllocate<true, true>(self, allocator, alloc_size, bytes_allocated, |
| usable_size); |
| if (ptr != nullptr) { |
| return ptr; |
| } |
| // Most allocations should have succeeded by now, so the heap is really full, really fragmented, |
| // or the requested size is really big. Do another GC, collecting SoftReferences this time. The |
| // VM spec requires that all SoftReferences have been collected and cleared before throwing |
| // OOME. |
| VLOG(gc) << "Forcing collection of SoftReferences for " << PrettySize(alloc_size) |
| << " allocation"; |
| // TODO: Run finalization, but this may cause more allocations to occur. |
| // We don't need a WaitForGcToComplete here either. |
| DCHECK(!gc_plan_.empty()); |
| CollectGarbageInternal(gc_plan_.back(), kGcCauseForAlloc, true); |
| if (was_default_allocator && allocator != GetCurrentAllocator()) { |
| return nullptr; |
| } |
| ptr = TryToAllocate<true, true>(self, allocator, alloc_size, bytes_allocated, usable_size); |
| if (ptr == nullptr) { |
| const uint64_t current_time = NanoTime(); |
| switch (allocator) { |
| case kAllocatorTypeRosAlloc: |
| // Fall-through. |
| case kAllocatorTypeDlMalloc: { |
| if (use_homogeneous_space_compaction_for_oom_ && |
| current_time - last_time_homogeneous_space_compaction_by_oom_ > |
| min_interval_homogeneous_space_compaction_by_oom_) { |
| last_time_homogeneous_space_compaction_by_oom_ = current_time; |
| HomogeneousSpaceCompactResult result = PerformHomogeneousSpaceCompact(); |
| switch (result) { |
| case HomogeneousSpaceCompactResult::kSuccess: |
| // If the allocation succeeded, we delayed an oom. |
| ptr = TryToAllocate<true, true>(self, allocator, alloc_size, bytes_allocated, |
| usable_size); |
| if (ptr != nullptr) { |
| count_delayed_oom_++; |
| } |
| break; |
| case HomogeneousSpaceCompactResult::kErrorReject: |
| // Reject due to disabled moving GC. |
| break; |
| case HomogeneousSpaceCompactResult::kErrorVMShuttingDown: |
| // Throw OOM by default. |
| break; |
| default: { |
| UNIMPLEMENTED(FATAL) << "homogeneous space compaction result: " |
| << static_cast<size_t>(result); |
| UNREACHABLE(); |
| } |
| } |
| // Always print that we ran homogeneous space compation since this can cause jank. |
| VLOG(heap) << "Ran heap homogeneous space compaction, " |
| << " requested defragmentation " |
| << count_requested_homogeneous_space_compaction_.LoadSequentiallyConsistent() |
| << " performed defragmentation " |
| << count_performed_homogeneous_space_compaction_.LoadSequentiallyConsistent() |
| << " ignored homogeneous space compaction " |
| << count_ignored_homogeneous_space_compaction_.LoadSequentiallyConsistent() |
| << " delayed count = " |
| << count_delayed_oom_.LoadSequentiallyConsistent(); |
| } |
| break; |
| } |
| case kAllocatorTypeNonMoving: { |
| // Try to transition the heap if the allocation failure was due to the space being full. |
| if (!IsOutOfMemoryOnAllocation<false>(allocator, alloc_size)) { |
| // If we aren't out of memory then the OOM was probably from the non moving space being |
| // full. Attempt to disable compaction and turn the main space into a non moving space. |
| DisableMovingGc(); |
| // If we are still a moving GC then something must have caused the transition to fail. |
| if (IsMovingGc(collector_type_)) { |
| MutexLock mu(self, *gc_complete_lock_); |
| // If we couldn't disable moving GC, just throw OOME and return null. |
| LOG(WARNING) << "Couldn't disable moving GC with disable GC count " |
| << disable_moving_gc_count_; |
| } else { |
| LOG(WARNING) << "Disabled moving GC due to the non moving space being full"; |
| ptr = TryToAllocate<true, true>(self, allocator, alloc_size, bytes_allocated, |
| usable_size); |
| } |
| } |
| break; |
| } |
| default: { |
| // Do nothing for others allocators. |
| } |
| } |
| } |
| // If the allocation hasn't succeeded by this point, throw an OOM error. |
| if (ptr == nullptr) { |
| ThrowOutOfMemoryError(self, alloc_size, allocator); |
| } |
| return ptr; |
| } |
| |
| void Heap::SetTargetHeapUtilization(float target) { |
| DCHECK_GT(target, 0.0f); // asserted in Java code |
| DCHECK_LT(target, 1.0f); |
| target_utilization_ = target; |
| } |
| |
| size_t Heap::GetObjectsAllocated() const { |
| size_t total = 0; |
| for (space::AllocSpace* space : alloc_spaces_) { |
| total += space->GetObjectsAllocated(); |
| } |
| return total; |
| } |
| |
| uint64_t Heap::GetObjectsAllocatedEver() const { |
| return GetObjectsFreedEver() + GetObjectsAllocated(); |
| } |
| |
| uint64_t Heap::GetBytesAllocatedEver() const { |
| return GetBytesFreedEver() + GetBytesAllocated(); |
| } |
| |
| class InstanceCounter { |
| public: |
| InstanceCounter(const std::vector<mirror::Class*>& classes, bool use_is_assignable_from, uint64_t* counts) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| : classes_(classes), use_is_assignable_from_(use_is_assignable_from), counts_(counts) { |
| } |
| static void Callback(mirror::Object* obj, void* arg) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { |
| InstanceCounter* instance_counter = reinterpret_cast<InstanceCounter*>(arg); |
| mirror::Class* instance_class = obj->GetClass(); |
| CHECK(instance_class != nullptr); |
| for (size_t i = 0; i < instance_counter->classes_.size(); ++i) { |
| if (instance_counter->use_is_assignable_from_) { |
| if (instance_counter->classes_[i]->IsAssignableFrom(instance_class)) { |
| ++instance_counter->counts_[i]; |
| } |
| } else if (instance_class == instance_counter->classes_[i]) { |
| ++instance_counter->counts_[i]; |
| } |
| } |
| } |
| |
| private: |
| const std::vector<mirror::Class*>& classes_; |
| bool use_is_assignable_from_; |
| uint64_t* const counts_; |
| DISALLOW_COPY_AND_ASSIGN(InstanceCounter); |
| }; |
| |
| void Heap::CountInstances(const std::vector<mirror::Class*>& classes, bool use_is_assignable_from, |
| uint64_t* counts) { |
| // Can't do any GC in this function since this may move classes. |
| ScopedAssertNoThreadSuspension ants(Thread::Current(), "CountInstances"); |
| InstanceCounter counter(classes, use_is_assignable_from, counts); |
| ReaderMutexLock mu(ants.Self(), *Locks::heap_bitmap_lock_); |
| VisitObjects(InstanceCounter::Callback, &counter); |
| } |
| |
| class InstanceCollector { |
| public: |
| InstanceCollector(mirror::Class* c, int32_t max_count, std::vector<mirror::Object*>& instances) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| : class_(c), max_count_(max_count), instances_(instances) { |
| } |
| static void Callback(mirror::Object* obj, void* arg) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { |
| DCHECK(arg != nullptr); |
| InstanceCollector* instance_collector = reinterpret_cast<InstanceCollector*>(arg); |
| if (obj->GetClass() == instance_collector->class_) { |
| if (instance_collector->max_count_ == 0 || |
| instance_collector->instances_.size() < instance_collector->max_count_) { |
| instance_collector->instances_.push_back(obj); |
| } |
| } |
| } |
| |
| private: |
| const mirror::Class* const class_; |
| const uint32_t max_count_; |
| std::vector<mirror::Object*>& instances_; |
| DISALLOW_COPY_AND_ASSIGN(InstanceCollector); |
| }; |
| |
| void Heap::GetInstances(mirror::Class* c, int32_t max_count, |
| std::vector<mirror::Object*>& instances) { |
| // Can't do any GC in this function since this may move classes. |
| ScopedAssertNoThreadSuspension ants(Thread::Current(), "GetInstances"); |
| InstanceCollector collector(c, max_count, instances); |
| ReaderMutexLock mu(ants.Self(), *Locks::heap_bitmap_lock_); |
| VisitObjects(&InstanceCollector::Callback, &collector); |
| } |
| |
| class ReferringObjectsFinder { |
| public: |
| ReferringObjectsFinder(mirror::Object* object, int32_t max_count, |
| std::vector<mirror::Object*>& referring_objects) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) |
| : object_(object), max_count_(max_count), referring_objects_(referring_objects) { |
| } |
| |
| static void Callback(mirror::Object* obj, void* arg) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { |
| reinterpret_cast<ReferringObjectsFinder*>(arg)->operator()(obj); |
| } |
| |
| // For bitmap Visit. |
| // TODO: Fix lock analysis to not use NO_THREAD_SAFETY_ANALYSIS, requires support for |
| // annotalysis on visitors. |
| void operator()(mirror::Object* o) const NO_THREAD_SAFETY_ANALYSIS { |
| o->VisitReferences<true>(*this, VoidFunctor()); |
| } |
| |
| // For Object::VisitReferences. |
| void operator()(mirror::Object* obj, MemberOffset offset, bool /* is_static */) const |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| mirror::Object* ref = obj->GetFieldObject<mirror::Object>(offset); |
| if (ref == object_ && (max_count_ == 0 || referring_objects_.size() < max_count_)) { |
| referring_objects_.push_back(obj); |
| } |
| } |
| |
| private: |
| const mirror::Object* const object_; |
| const uint32_t max_count_; |
| std::vector<mirror::Object*>& referring_objects_; |
| DISALLOW_COPY_AND_ASSIGN(ReferringObjectsFinder); |
| }; |
| |
| void Heap::GetReferringObjects(mirror::Object* o, int32_t max_count, |
| std::vector<mirror::Object*>& referring_objects) { |
| // Can't do any GC in this function since this may move the object o. |
| ScopedAssertNoThreadSuspension ants(Thread::Current(), "GetReferringObjects"); |
| ReferringObjectsFinder finder(o, max_count, referring_objects); |
| ReaderMutexLock mu(ants.Self(), *Locks::heap_bitmap_lock_); |
| VisitObjects(&ReferringObjectsFinder::Callback, &finder); |
| } |
| |
| void Heap::CollectGarbage(bool clear_soft_references) { |
| // Even if we waited for a GC we still need to do another GC since weaks allocated during the |
| // last GC will not have necessarily been cleared. |
| CollectGarbageInternal(gc_plan_.back(), kGcCauseExplicit, clear_soft_references); |
| } |
| |
| HomogeneousSpaceCompactResult Heap::PerformHomogeneousSpaceCompact() { |
| Thread* self = Thread::Current(); |
| // Inc requested homogeneous space compaction. |
| count_requested_homogeneous_space_compaction_++; |
| // Store performed homogeneous space compaction at a new request arrival. |
| ThreadList* tl = Runtime::Current()->GetThreadList(); |
| ScopedThreadStateChange tsc(self, kWaitingPerformingGc); |
| Locks::mutator_lock_->AssertNotHeld(self); |
| { |
| ScopedThreadStateChange tsc(self, kWaitingForGcToComplete); |
| MutexLock mu(self, *gc_complete_lock_); |
| // Ensure there is only one GC at a time. |
| WaitForGcToCompleteLocked(kGcCauseHomogeneousSpaceCompact, self); |
| // Homogeneous space compaction is a copying transition, can't run it if the moving GC disable count |
| // is non zero. |
| // If the collector type changed to something which doesn't benefit from homogeneous space compaction, |
| // exit. |
| if (disable_moving_gc_count_ != 0 || IsMovingGc(collector_type_) || |
| !main_space_->CanMoveObjects()) { |
| return HomogeneousSpaceCompactResult::kErrorReject; |
| } |
| collector_type_running_ = kCollectorTypeHomogeneousSpaceCompact; |
| } |
| if (Runtime::Current()->IsShuttingDown(self)) { |
| // Don't allow heap transitions to happen if the runtime is shutting down since these can |
| // cause objects to get finalized. |
| FinishGC(self, collector::kGcTypeNone); |
| return HomogeneousSpaceCompactResult::kErrorVMShuttingDown; |
| } |
| // Suspend all threads. |
| tl->SuspendAll(); |
| uint64_t start_time = NanoTime(); |
| // Launch compaction. |
| space::MallocSpace* to_space = main_space_backup_.release(); |
| space::MallocSpace* from_space = main_space_; |
| to_space->GetMemMap()->Protect(PROT_READ | PROT_WRITE); |
| const uint64_t space_size_before_compaction = from_space->Size(); |
| AddSpace(to_space); |
| Compact(to_space, from_space, kGcCauseHomogeneousSpaceCompact); |
| // Leave as prot read so that we can still run ROSAlloc verification on this space. |
| from_space->GetMemMap()->Protect(PROT_READ); |
| const uint64_t space_size_after_compaction = to_space->Size(); |
| main_space_ = to_space; |
| main_space_backup_.reset(from_space); |
| RemoveSpace(from_space); |
| SetSpaceAsDefault(main_space_); // Set as default to reset the proper dlmalloc space. |
| // Update performed homogeneous space compaction count. |
| count_performed_homogeneous_space_compaction_++; |
| // Print statics log and resume all threads. |
| uint64_t duration = NanoTime() - start_time; |
| VLOG(heap) << "Heap homogeneous space compaction took " << PrettyDuration(duration) << " size: " |
| << PrettySize(space_size_before_compaction) << " -> " |
| << PrettySize(space_size_after_compaction) << " compact-ratio: " |
| << std::fixed << static_cast<double>(space_size_after_compaction) / |
| static_cast<double>(space_size_before_compaction); |
| tl->ResumeAll(); |
| // Finish GC. |
| reference_processor_.EnqueueClearedReferences(self); |
| GrowForUtilization(semi_space_collector_); |
| FinishGC(self, collector::kGcTypeFull); |
| return HomogeneousSpaceCompactResult::kSuccess; |
| } |
| |
| |
| void Heap::TransitionCollector(CollectorType collector_type) { |
| if (collector_type == collector_type_) { |
| return; |
| } |
| VLOG(heap) << "TransitionCollector: " << static_cast<int>(collector_type_) |
| << " -> " << static_cast<int>(collector_type); |
| uint64_t start_time = NanoTime(); |
| uint32_t before_allocated = num_bytes_allocated_.LoadSequentiallyConsistent(); |
| Runtime* const runtime = Runtime::Current(); |
| ThreadList* const tl = runtime->GetThreadList(); |
| Thread* const self = Thread::Current(); |
| ScopedThreadStateChange tsc(self, kWaitingPerformingGc); |
| Locks::mutator_lock_->AssertNotHeld(self); |
| // Busy wait until we can GC (StartGC can fail if we have a non-zero |
| // compacting_gc_disable_count_, this should rarely occurs). |
| for (;;) { |
| { |
| ScopedThreadStateChange tsc(self, kWaitingForGcToComplete); |
| MutexLock mu(self, *gc_complete_lock_); |
| // Ensure there is only one GC at a time. |
| WaitForGcToCompleteLocked(kGcCauseCollectorTransition, self); |
| // Currently we only need a heap transition if we switch from a moving collector to a |
| // non-moving one, or visa versa. |
| const bool copying_transition = IsMovingGc(collector_type_) != IsMovingGc(collector_type); |
| // If someone else beat us to it and changed the collector before we could, exit. |
| // This is safe to do before the suspend all since we set the collector_type_running_ before |
| // we exit the loop. If another thread attempts to do the heap transition before we exit, |
| // then it would get blocked on WaitForGcToCompleteLocked. |
| if (collector_type == collector_type_) { |
| return; |
| } |
| // GC can be disabled if someone has a used GetPrimitiveArrayCritical but not yet released. |
| if (!copying_transition || disable_moving_gc_count_ == 0) { |
| // TODO: Not hard code in semi-space collector? |
| collector_type_running_ = copying_transition ? kCollectorTypeSS : collector_type; |
| break; |
| } |
| } |
| usleep(1000); |
| } |
| if (runtime->IsShuttingDown(self)) { |
| // Don't allow heap transitions to happen if the runtime is shutting down since these can |
| // cause objects to get finalized. |
| FinishGC(self, collector::kGcTypeNone); |
| return; |
| } |
| tl->SuspendAll(); |
| switch (collector_type) { |
| case kCollectorTypeSS: { |
| if (!IsMovingGc(collector_type_)) { |
| // Create the bump pointer space from the backup space. |
| CHECK(main_space_backup_ != nullptr); |
| std::unique_ptr<MemMap> mem_map(main_space_backup_->ReleaseMemMap()); |
| // We are transitioning from non moving GC -> moving GC, since we copied from the bump |
| // pointer space last transition it will be protected. |
| CHECK(mem_map != nullptr); |
| mem_map->Protect(PROT_READ | PROT_WRITE); |
| bump_pointer_space_ = space::BumpPointerSpace::CreateFromMemMap("Bump pointer space", |
| mem_map.release()); |
| AddSpace(bump_pointer_space_); |
| Compact(bump_pointer_space_, main_space_, kGcCauseCollectorTransition); |
| // Use the now empty main space mem map for the bump pointer temp space. |
| mem_map.reset(main_space_->ReleaseMemMap()); |
| // Unset the pointers just in case. |
| if (dlmalloc_space_ == main_space_) { |
| dlmalloc_space_ = nullptr; |
| } else if (rosalloc_space_ == main_space_) { |
| rosalloc_space_ = nullptr; |
| } |
| // Remove the main space so that we don't try to trim it, this doens't work for debug |
| // builds since RosAlloc attempts to read the magic number from a protected page. |
| RemoveSpace(main_space_); |
| RemoveRememberedSet(main_space_); |
| delete main_space_; // Delete the space since it has been removed. |
| main_space_ = nullptr; |
| RemoveRememberedSet(main_space_backup_.get()); |
| main_space_backup_.reset(nullptr); // Deletes the space. |
| temp_space_ = space::BumpPointerSpace::CreateFromMemMap("Bump pointer space 2", |
| mem_map.release()); |
| AddSpace(temp_space_); |
| } |
| break; |
| } |
| case kCollectorTypeMS: |
| // Fall through. |
| case kCollectorTypeCMS: { |
| if (IsMovingGc(collector_type_)) { |
| CHECK(temp_space_ != nullptr); |
| std::unique_ptr<MemMap> mem_map(temp_space_->ReleaseMemMap()); |
| RemoveSpace(temp_space_); |
| temp_space_ = nullptr; |
| mem_map->Protect(PROT_READ | PROT_WRITE); |
| CreateMainMallocSpace(mem_map.get(), kDefaultInitialSize, mem_map->Size(), |
| mem_map->Size()); |
| mem_map.release(); |
| // Compact to the main space from the bump pointer space, don't need to swap semispaces. |
| AddSpace(main_space_); |
| Compact(main_space_, bump_pointer_space_, kGcCauseCollectorTransition); |
| mem_map.reset(bump_pointer_space_->ReleaseMemMap()); |
| RemoveSpace(bump_pointer_space_); |
| bump_pointer_space_ = nullptr; |
| const char* name = kUseRosAlloc ? kRosAllocSpaceName[1] : kDlMallocSpaceName[1]; |
| // Temporarily unprotect the backup mem map so rosalloc can write the debug magic number. |
| if (kIsDebugBuild && kUseRosAlloc) { |
| mem_map->Protect(PROT_READ | PROT_WRITE); |
| } |
| main_space_backup_.reset(CreateMallocSpaceFromMemMap(mem_map.get(), kDefaultInitialSize, |
| mem_map->Size(), mem_map->Size(), |
| name, true)); |
| if (kIsDebugBuild && kUseRosAlloc) { |
| mem_map->Protect(PROT_NONE); |
| } |
| mem_map.release(); |
| } |
| break; |
| } |
| default: { |
| LOG(FATAL) << "Attempted to transition to invalid collector type " |
| << static_cast<size_t>(collector_type); |
| break; |
| } |
| } |
| ChangeCollector(collector_type); |
| tl->ResumeAll(); |
| // Can't call into java code with all threads suspended. |
| reference_processor_.EnqueueClearedReferences(self); |
| uint64_t duration = NanoTime() - start_time; |
| GrowForUtilization(semi_space_collector_); |
| FinishGC(self, collector::kGcTypeFull); |
| int32_t after_allocated = num_bytes_allocated_.LoadSequentiallyConsistent(); |
| int32_t delta_allocated = before_allocated - after_allocated; |
| std::string saved_str; |
| if (delta_allocated >= 0) { |
| saved_str = " saved at least " + PrettySize(delta_allocated); |
| } else { |
| saved_str = " expanded " + PrettySize(-delta_allocated); |
| } |
| VLOG(heap) << "Heap transition to " << process_state_ << " took " |
| << PrettyDuration(duration) << saved_str; |
| } |
| |
| void Heap::ChangeCollector(CollectorType collector_type) { |
| // TODO: Only do this with all mutators suspended to avoid races. |
| if (collector_type != collector_type_) { |
| if (collector_type == kCollectorTypeMC) { |
| // Don't allow mark compact unless support is compiled in. |
| CHECK(kMarkCompactSupport); |
| } |
| collector_type_ = collector_type; |
| gc_plan_.clear(); |
| switch (collector_type_) { |
| case kCollectorTypeCC: // Fall-through. |
| case kCollectorTypeMC: // Fall-through. |
| case kCollectorTypeSS: // Fall-through. |
| case kCollectorTypeGSS: { |
| gc_plan_.push_back(collector::kGcTypeFull); |
| if (use_tlab_) { |
| ChangeAllocator(kAllocatorTypeTLAB); |
| } else { |
| ChangeAllocator(kAllocatorTypeBumpPointer); |
| } |
| break; |
| } |
| case kCollectorTypeMS: { |
| gc_plan_.push_back(collector::kGcTypeSticky); |
| gc_plan_.push_back(collector::kGcTypePartial); |
| gc_plan_.push_back(collector::kGcTypeFull); |
| ChangeAllocator(kUseRosAlloc ? kAllocatorTypeRosAlloc : kAllocatorTypeDlMalloc); |
| break; |
| } |
| case kCollectorTypeCMS: { |
| gc_plan_.push_back(collector::kGcTypeSticky); |
| gc_plan_.push_back(collector::kGcTypePartial); |
| gc_plan_.push_back(collector::kGcTypeFull); |
| ChangeAllocator(kUseRosAlloc ? kAllocatorTypeRosAlloc : kAllocatorTypeDlMalloc); |
| break; |
| } |
| default: { |
| UNIMPLEMENTED(FATAL); |
| UNREACHABLE(); |
| } |
| } |
| if (IsGcConcurrent()) { |
| concurrent_start_bytes_ = |
| std::max(max_allowed_footprint_, kMinConcurrentRemainingBytes) - kMinConcurrentRemainingBytes; |
| } else { |
| concurrent_start_bytes_ = std::numeric_limits<size_t>::max(); |
| } |
| } |
| } |
| |
| // Special compacting collector which uses sub-optimal bin packing to reduce zygote space size. |
| class ZygoteCompactingCollector FINAL : public collector::SemiSpace { |
| public: |
| explicit ZygoteCompactingCollector(gc::Heap* heap) : SemiSpace(heap, false, "zygote collector"), |
| bin_live_bitmap_(nullptr), bin_mark_bitmap_(nullptr) { |
| } |
| |
| void BuildBins(space::ContinuousSpace* space) { |
| bin_live_bitmap_ = space->GetLiveBitmap(); |
| bin_mark_bitmap_ = space->GetMarkBitmap(); |
| BinContext context; |
| context.prev_ = reinterpret_cast<uintptr_t>(space->Begin()); |
| context.collector_ = this; |
| WriterMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); |
| // Note: This requires traversing the space in increasing order of object addresses. |
| bin_live_bitmap_->Walk(Callback, reinterpret_cast<void*>(&context)); |
| // Add the last bin which spans after the last object to the end of the space. |
| AddBin(reinterpret_cast<uintptr_t>(space->End()) - context.prev_, context.prev_); |
| } |
| |
| private: |
| struct BinContext { |
| uintptr_t prev_; // The end of the previous object. |
| ZygoteCompactingCollector* collector_; |
| }; |
| // Maps from bin sizes to locations. |
| std::multimap<size_t, uintptr_t> bins_; |
| // Live bitmap of the space which contains the bins. |
| accounting::ContinuousSpaceBitmap* bin_live_bitmap_; |
| // Mark bitmap of the space which contains the bins. |
| accounting::ContinuousSpaceBitmap* bin_mark_bitmap_; |
| |
| static void Callback(mirror::Object* obj, void* arg) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| DCHECK(arg != nullptr); |
| BinContext* context = reinterpret_cast<BinContext*>(arg); |
| ZygoteCompactingCollector* collector = context->collector_; |
| uintptr_t object_addr = reinterpret_cast<uintptr_t>(obj); |
| size_t bin_size = object_addr - context->prev_; |
| // Add the bin consisting of the end of the previous object to the start of the current object. |
| collector->AddBin(bin_size, context->prev_); |
| context->prev_ = object_addr + RoundUp(obj->SizeOf(), kObjectAlignment); |
| } |
| |
| void AddBin(size_t size, uintptr_t position) { |
| if (size != 0) { |
| bins_.insert(std::make_pair(size, position)); |
| } |
| } |
| |
| virtual bool ShouldSweepSpace(space::ContinuousSpace* space) const { |
| // Don't sweep any spaces since we probably blasted the internal accounting of the free list |
| // allocator. |
| UNUSED(space); |
| return false; |
| } |
| |
| virtual mirror::Object* MarkNonForwardedObject(mirror::Object* obj) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) { |
| size_t object_size = RoundUp(obj->SizeOf(), kObjectAlignment); |
| mirror::Object* forward_address; |
| // Find the smallest bin which we can move obj in. |
| auto it = bins_.lower_bound(object_size); |
| if (it == bins_.end()) { |
| // No available space in the bins, place it in the target space instead (grows the zygote |
| // space). |
| size_t bytes_allocated; |
| forward_address = to_space_->Alloc(self_, object_size, &bytes_allocated, nullptr); |
| if (to_space_live_bitmap_ != nullptr) { |
| to_space_live_bitmap_->Set(forward_address); |
| } else { |
| GetHeap()->GetNonMovingSpace()->GetLiveBitmap()->Set(forward_address); |
| GetHeap()->GetNonMovingSpace()->GetMarkBitmap()->Set(forward_address); |
| } |
| } else { |
| size_t size = it->first; |
| uintptr_t pos = it->second; |
| bins_.erase(it); // Erase the old bin which we replace with the new smaller bin. |
| forward_address = reinterpret_cast<mirror::Object*>(pos); |
| // Set the live and mark bits so that sweeping system weaks works properly. |
| bin_live_bitmap_->Set(forward_address); |
| bin_mark_bitmap_->Set(forward_address); |
| DCHECK_GE(size, object_size); |
| AddBin(size - object_size, pos + object_size); // Add a new bin with the remaining space. |
| } |
| // Copy the object over to its new location. |
| memcpy(reinterpret_cast<void*>(forward_address), obj, object_size); |
| if (kUseBakerOrBrooksReadBarrier) { |
| obj->AssertReadBarrierPointer(); |
| if (kUseBrooksReadBarrier) { |
| DCHECK_EQ(forward_address->GetReadBarrierPointer(), obj); |
| forward_address->SetReadBarrierPointer(forward_address); |
| } |
| forward_address->AssertReadBarrierPointer(); |
| } |
| return forward_address; |
| } |
| }; |
| |
| void Heap::UnBindBitmaps() { |
| TimingLogger::ScopedTiming t("UnBindBitmaps", GetCurrentGcIteration()->GetTimings()); |
| for (const auto& space : GetContinuousSpaces()) { |
| if (space->IsContinuousMemMapAllocSpace()) { |
| space::ContinuousMemMapAllocSpace* alloc_space = space->AsContinuousMemMapAllocSpace(); |
| if (alloc_space->HasBoundBitmaps()) { |
| alloc_space->UnBindBitmaps(); |
| } |
| } |
| } |
| } |
| |
| void Heap::PreZygoteFork() { |
| CollectGarbageInternal(collector::kGcTypeFull, kGcCauseBackground, false); |
| Thread* self = Thread::Current(); |
| MutexLock mu(self, zygote_creation_lock_); |
| // Try to see if we have any Zygote spaces. |
| if (HasZygoteSpace()) { |
| LOG(WARNING) << __FUNCTION__ << " called when we already have a zygote space."; |
| return; |
| } |
| Runtime::Current()->GetInternTable()->SwapPostZygoteWithPreZygote(); |
| VLOG(heap) << "Starting PreZygoteFork"; |
| // Trim the pages at the end of the non moving space. |
| non_moving_space_->Trim(); |
| // The end of the non-moving space may be protected, unprotect it so that we can copy the zygote |
| // there. |
| non_moving_space_->GetMemMap()->Protect(PROT_READ | PROT_WRITE); |
| const bool same_space = non_moving_space_ == main_space_; |
| if (kCompactZygote) { |
| // Can't compact if the non moving space is the same as the main space. |
| DCHECK(semi_space_collector_ != nullptr); |
| // Temporarily disable rosalloc verification because the zygote |
| // compaction will mess up the rosalloc internal metadata. |
| ScopedDisableRosAllocVerification disable_rosalloc_verif(this); |
| ZygoteCompactingCollector zygote_collector(this); |
| zygote_collector.BuildBins(non_moving_space_); |
| // Create a new bump pointer space which we will compact into. |
| space::BumpPointerSpace target_space("zygote bump space", non_moving_space_->End(), |
| non_moving_space_->Limit()); |
| // Compact the bump pointer space to a new zygote bump pointer space. |
| bool reset_main_space = false; |
| if (IsMovingGc(collector_type_)) { |
| zygote_collector.SetFromSpace(bump_pointer_space_); |
| } else { |
| CHECK(main_space_ != nullptr); |
| // Copy from the main space. |
| zygote_collector.SetFromSpace(main_space_); |
| reset_main_space = true; |
| } |
| zygote_collector.SetToSpace(&target_space); |
| zygote_collector.SetSwapSemiSpaces(false); |
| zygote_collector.Run(kGcCauseCollectorTransition, false); |
| if (reset_main_space) { |
| main_space_->GetMemMap()->Protect(PROT_READ | PROT_WRITE); |
| madvise(main_space_->Begin(), main_space_->Capacity(), MADV_DONTNEED); |
| MemMap* mem_map = main_space_->ReleaseMemMap(); |
| RemoveSpace(main_space_); |
| space::Space* old_main_space = main_space_; |
| CreateMainMallocSpace(mem_map, kDefaultInitialSize, mem_map->Size(), mem_map->Size()); |
| delete old_main_space; |
| AddSpace(main_space_); |
| } else { |
| bump_pointer_space_->GetMemMap()->Protect(PROT_READ | PROT_WRITE); |
| } |
| if (temp_space_ != nullptr) { |
| CHECK(temp_space_->IsEmpty()); |
| } |
| total_objects_freed_ever_ += GetCurrentGcIteration()->GetFreedObjects(); |
| total_bytes_freed_ever_ += GetCurrentGcIteration()->GetFreedBytes(); |
| // Update the end and write out image. |
| non_moving_space_->SetEnd(target_space.End()); |
| non_moving_space_->SetLimit(target_space.Limit()); |
| VLOG(heap) << "Zygote space size " << non_moving_space_->Size() << " bytes"; |
| } |
| // Change the collector to the post zygote one. |
| ChangeCollector(foreground_collector_type_); |
| // Save the old space so that we can remove it after we complete creating the zygote space. |
| space::MallocSpace* old_alloc_space = non_moving_space_; |
| // Turn the current alloc space into a zygote space and obtain the new alloc space composed of |
| // the remaining available space. |
| // Remove the old space before creating the zygote space since creating the zygote space sets |
| // the old alloc space's bitmaps to nullptr. |
| RemoveSpace(old_alloc_space); |
| if (collector::SemiSpace::kUseRememberedSet) { |
| // Sanity bound check. |
| FindRememberedSetFromSpace(old_alloc_space)->AssertAllDirtyCardsAreWithinSpace(); |
| // Remove the remembered set for the now zygote space (the old |
| // non-moving space). Note now that we have compacted objects into |
| // the zygote space, the data in the remembered set is no longer |
| // needed. The zygote space will instead have a mod-union table |
| // from this point on. |
| RemoveRememberedSet(old_alloc_space); |
| } |
| zygote_space_ = old_alloc_space->CreateZygoteSpace("alloc space", low_memory_mode_, |
| &non_moving_space_); |
| CHECK(!non_moving_space_->CanMoveObjects()); |
| if (same_space) { |
| main_space_ = non_moving_space_; |
| SetSpaceAsDefault(main_space_); |
| } |
| delete old_alloc_space; |
| CHECK(HasZygoteSpace()) << "Failed creating zygote space"; |
| AddSpace(zygote_space_); |
| non_moving_space_->SetFootprintLimit(non_moving_space_->Capacity()); |
| AddSpace(non_moving_space_); |
| // Create the zygote space mod union table. |
| accounting::ModUnionTable* mod_union_table = |
| new accounting::ModUnionTableCardCache("zygote space mod-union table", this, |
| zygote_space_); |
| CHECK(mod_union_table != nullptr) << "Failed to create zygote space mod-union table"; |
| // Set all the cards in the mod-union table since we don't know which objects contain references |
| // to large objects. |
| mod_union_table->SetCards(); |
| AddModUnionTable(mod_union_table); |
| if (collector::SemiSpace::kUseRememberedSet) { |
| // Add a new remembered set for the post-zygote non-moving space. |
| accounting::RememberedSet* post_zygote_non_moving_space_rem_set = |
| new accounting::RememberedSet("Post-zygote non-moving space remembered set", this, |
| non_moving_space_); |
| CHECK(post_zygote_non_moving_space_rem_set != nullptr) |
| << "Failed to create post-zygote non-moving space remembered set"; |
| AddRememberedSet(post_zygote_non_moving_space_rem_set); |
| } |
| } |
| |
| void Heap::FlushAllocStack() { |
| MarkAllocStackAsLive(allocation_stack_.get()); |
| allocation_stack_->Reset(); |
| } |
| |
| void Heap::MarkAllocStack(accounting::ContinuousSpaceBitmap* bitmap1, |
| accounting::ContinuousSpaceBitmap* bitmap2, |
| accounting::LargeObjectBitmap* large_objects, |
| accounting::ObjectStack* stack) { |
| DCHECK(bitmap1 != nullptr); |
| DCHECK(bitmap2 != nullptr); |
| mirror::Object** limit = stack->End(); |
| for (mirror::Object** it = stack->Begin(); it != limit; ++it) { |
| const mirror::Object* obj = *it; |
| if (!kUseThreadLocalAllocationStack || obj != nullptr) { |
| if (bitmap1->HasAddress(obj)) { |
| bitmap1->Set(obj); |
| } else if (bitmap2->HasAddress(obj)) { |
| bitmap2->Set(obj); |
| } else { |
| DCHECK(large_objects != nullptr); |
| large_objects->Set(obj); |
| } |
| } |
| } |
| } |
| |
| void Heap::SwapSemiSpaces() { |
| CHECK(bump_pointer_space_ != nullptr); |
| CHECK(temp_space_ != nullptr); |
| std::swap(bump_pointer_space_, temp_space_); |
| } |
| |
| void Heap::Compact(space::ContinuousMemMapAllocSpace* target_space, |
| space::ContinuousMemMapAllocSpace* source_space, |
| GcCause gc_cause) { |
| CHECK(kMovingCollector); |
| if (target_space != source_space) { |
| // Don't swap spaces since this isn't a typical semi space collection. |
| semi_space_collector_->SetSwapSemiSpaces(false); |
| semi_space_collector_->SetFromSpace(source_space); |
| semi_space_collector_->SetToSpace(target_space); |
| semi_space_collector_->Run(gc_cause, false); |
| } else { |
| CHECK(target_space->IsBumpPointerSpace()) |
| << "In-place compaction is only supported for bump pointer spaces"; |
| mark_compact_collector_->SetSpace(target_space->AsBumpPointerSpace()); |
| mark_compact_collector_->Run(kGcCauseCollectorTransition, false); |
| } |
| } |
| |
| collector::GcType Heap::CollectGarbageInternal(collector::GcType gc_type, GcCause gc_cause, |
| bool clear_soft_references) { |
| Thread* self = Thread::Current(); |
| Runtime* runtime = Runtime::Current(); |
| // If the heap can't run the GC, silently fail and return that no GC was run. |
| switch (gc_type) { |
| case collector::kGcTypePartial: { |
| if (!HasZygoteSpace()) { |
| return collector::kGcTypeNone; |
| } |
| break; |
| } |
| default: { |
| // Other GC types don't have any special cases which makes them not runnable. The main case |
| // here is full GC. |
| } |
| } |
| ScopedThreadStateChange tsc(self, kWaitingPerformingGc); |
| Locks::mutator_lock_->AssertNotHeld(self); |
| if (self->IsHandlingStackOverflow()) { |
| LOG(WARNING) << "Performing GC on a thread that is handling a stack overflow."; |
| } |
| bool compacting_gc; |
| { |
| gc_complete_lock_->AssertNotHeld(self); |
| ScopedThreadStateChange tsc(self, kWaitingForGcToComplete); |
| MutexLock mu(self, *gc_complete_lock_); |
| // Ensure there is only one GC at a time. |
| WaitForGcToCompleteLocked(gc_cause, self); |
| compacting_gc = IsMovingGc(collector_type_); |
| // GC can be disabled if someone has a used GetPrimitiveArrayCritical. |
| if (compacting_gc && disable_moving_gc_count_ != 0) { |
| LOG(WARNING) << "Skipping GC due to disable moving GC count " << disable_moving_gc_count_; |
| return collector::kGcTypeNone; |
| } |
| collector_type_running_ = collector_type_; |
| } |
| |
| if (gc_cause == kGcCauseForAlloc && runtime->HasStatsEnabled()) { |
| ++runtime->GetStats()->gc_for_alloc_count; |
| ++self->GetStats()->gc_for_alloc_count; |
| } |
| uint64_t gc_start_time_ns = NanoTime(); |
| uint64_t gc_start_size = GetBytesAllocated(); |
| // Approximate allocation rate in bytes / second. |
| uint64_t ms_delta = NsToMs(gc_start_time_ns - last_gc_time_ns_); |
| // Back to back GCs can cause 0 ms of wait time in between GC invocations. |
| if (LIKELY(ms_delta != 0)) { |
| allocation_rate_ = ((gc_start_size - last_gc_size_) * 1000) / ms_delta; |
| ATRACE_INT("Allocation rate KB/s", allocation_rate_ / KB); |
| VLOG(heap) << "Allocation rate: " << PrettySize(allocation_rate_) << "/s"; |
| } |
| |
| DCHECK_LT(gc_type, collector::kGcTypeMax); |
| DCHECK_NE(gc_type, collector::kGcTypeNone); |
| |
| collector::GarbageCollector* collector = nullptr; |
| // TODO: Clean this up. |
| if (compacting_gc) { |
| DCHECK(current_allocator_ == kAllocatorTypeBumpPointer || |
| current_allocator_ == kAllocatorTypeTLAB); |
| switch (collector_type_) { |
| case kCollectorTypeSS: |
| // Fall-through. |
| case kCollectorTypeGSS: |
| semi_space_collector_->SetFromSpace(bump_pointer_space_); |
| semi_space_collector_->SetToSpace(temp_space_); |
| semi_space_collector_->SetSwapSemiSpaces(true); |
| collector = semi_space_collector_; |
| break; |
| case kCollectorTypeCC: |
| collector = concurrent_copying_collector_; |
| break; |
| case kCollectorTypeMC: |
| mark_compact_collector_->SetSpace(bump_pointer_space_); |
| collector = mark_compact_collector_; |
| break; |
| default: |
| LOG(FATAL) << "Invalid collector type " << static_cast<size_t>(collector_type_); |
| } |
| if (collector != mark_compact_collector_) { |
| temp_space_->GetMemMap()->Protect(PROT_READ | PROT_WRITE); |
| CHECK(temp_space_->IsEmpty()); |
| } |
| gc_type = collector::kGcTypeFull; // TODO: Not hard code this in. |
| } else if (current_allocator_ == kAllocatorTypeRosAlloc || |
| current_allocator_ == kAllocatorTypeDlMalloc) { |
| collector = FindCollectorByGcType(gc_type); |
| } else { |
| LOG(FATAL) << "Invalid current allocator " << current_allocator_; |
| } |
| if (IsGcConcurrent()) { |
| // Disable concurrent GC check so that we don't have spammy JNI requests. |
| // This gets recalculated in GrowForUtilization. It is important that it is disabled / |
| // calculated in the same thread so that there aren't any races that can cause it to become |
| // permanantly disabled. b/17942071 |
| concurrent_start_bytes_ = std::numeric_limits<size_t>::max(); |
| } |
| CHECK(collector != nullptr) |
| << "Could not find garbage collector with collector_type=" |
| << static_cast<size_t>(collector_type_) << " and gc_type=" << gc_type; |
| collector->Run(gc_cause, clear_soft_references || runtime->IsZygote()); |
| total_objects_freed_ever_ += GetCurrentGcIteration()->GetFreedObjects(); |
| total_bytes_freed_ever_ += GetCurrentGcIteration()->GetFreedBytes(); |
| RequestHeapTrim(); |
| // Enqueue cleared references. |
| reference_processor_.EnqueueClearedReferences(self); |
| // Grow the heap so that we know when to perform the next GC. |
| GrowForUtilization(collector); |
| const size_t duration = GetCurrentGcIteration()->GetDurationNs(); |
| const std::vector<uint64_t>& pause_times = GetCurrentGcIteration()->GetPauseTimes(); |
| // Print the GC if it is an explicit GC (e.g. Runtime.gc()) or a slow GC |
| // (mutator time blocked >= long_pause_log_threshold_). |
| bool log_gc = gc_cause == kGcCauseExplicit; |
| if (!log_gc && CareAboutPauseTimes()) { |
| // GC for alloc pauses the allocating thread, so consider it as a pause. |
| log_gc = duration > long_gc_log_threshold_ || |
| (gc_cause == kGcCauseForAlloc && duration > long_pause_log_threshold_); |
| for (uint64_t pause : pause_times) { |
| log_gc = log_gc || pause >= long_pause_log_threshold_; |
| } |
| } |
| if (log_gc) { |
| const size_t percent_free = GetPercentFree(); |
| const size_t current_heap_size = GetBytesAllocated(); |
| const size_t total_memory = GetTotalMemory(); |
| std::ostringstream pause_string; |
| for (size_t i = 0; i < pause_times.size(); ++i) { |
| pause_string << PrettyDuration((pause_times[i] / 1000) * 1000) |
| << ((i != pause_times.size() - 1) ? "," : ""); |
| } |
| LOG(INFO) << gc_cause << " " << collector->GetName() |
| << " GC freed " << current_gc_iteration_.GetFreedObjects() << "(" |
| << PrettySize(current_gc_iteration_.GetFreedBytes()) << ") AllocSpace objects, " |
| << current_gc_iteration_.GetFreedLargeObjects() << "(" |
| << PrettySize(current_gc_iteration_.GetFreedLargeObjectBytes()) << ") LOS objects, " |
| << percent_free << "% free, " << PrettySize(current_heap_size) << "/" |
| << PrettySize(total_memory) << ", " << "paused " << pause_string.str() |
| << " total " << PrettyDuration((duration / 1000) * 1000); |
| VLOG(heap) << Dumpable<TimingLogger>(*current_gc_iteration_.GetTimings()); |
| } |
| FinishGC(self, gc_type); |
| // Inform DDMS that a GC completed. |
| Dbg::GcDidFinish(); |
| return gc_type; |
| } |
| |
| void Heap::FinishGC(Thread* self, collector::GcType gc_type) { |
| MutexLock mu(self, *gc_complete_lock_); |
| collector_type_running_ = kCollectorTypeNone; |
| if (gc_type != collector::kGcTypeNone) { |
| last_gc_type_ = gc_type; |
| } |
| // Wake anyone who may have been waiting for the GC to complete. |
| gc_complete_cond_->Broadcast(self); |
| } |
| |
| static void RootMatchesObjectVisitor(mirror::Object** root, void* arg, uint32_t /*thread_id*/, |
| RootType /*root_type*/) { |
| mirror::Object* obj = reinterpret_cast<mirror::Object*>(arg); |
| if (*root == obj) { |
| LOG(INFO) << "Object " << obj << " is a root"; |
| } |
| } |
| |
| class ScanVisitor { |
| public: |
| void operator()(const mirror::Object* obj) const { |
| LOG(ERROR) << "Would have rescanned object " << obj; |
| } |
| }; |
| |
| // Verify a reference from an object. |
| class VerifyReferenceVisitor { |
| public: |
| explicit VerifyReferenceVisitor(Heap* heap, Atomic<size_t>* fail_count, bool verify_referent) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) |
| : heap_(heap), fail_count_(fail_count), verify_referent_(verify_referent) {} |
| |
| size_t GetFailureCount() const { |
| return fail_count_->LoadSequentiallyConsistent(); |
| } |
| |
| void operator()(mirror::Class* klass, mirror::Reference* ref) const |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| UNUSED(klass); |
| if (verify_referent_) { |
| VerifyReference(ref, ref->GetReferent(), mirror::Reference::ReferentOffset()); |
| } |
| } |
| |
| void operator()(mirror::Object* obj, MemberOffset offset, bool /*is_static*/) const |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| VerifyReference(obj, obj->GetFieldObject<mirror::Object>(offset), offset); |
| } |
| |
| bool IsLive(mirror::Object* obj) const NO_THREAD_SAFETY_ANALYSIS { |
| return heap_->IsLiveObjectLocked(obj, true, false, true); |
| } |
| |
| static void VerifyRootCallback(mirror::Object** root, void* arg, uint32_t thread_id, |
| RootType root_type) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| VerifyReferenceVisitor* visitor = reinterpret_cast<VerifyReferenceVisitor*>(arg); |
| if (!visitor->VerifyReference(nullptr, *root, MemberOffset(0))) { |
| LOG(ERROR) << "Root " << *root << " is dead with type " << PrettyTypeOf(*root) |
| << " thread_id= " << thread_id << " root_type= " << root_type; |
| } |
| } |
| |
| private: |
| // TODO: Fix the no thread safety analysis. |
| // Returns false on failure. |
| bool VerifyReference(mirror::Object* obj, mirror::Object* ref, MemberOffset offset) const |
| NO_THREAD_SAFETY_ANALYSIS { |
| if (ref == nullptr || IsLive(ref)) { |
| // Verify that the reference is live. |
| return true; |
| } |
| if (fail_count_->FetchAndAddSequentiallyConsistent(1) == 0) { |
| // Print message on only on first failure to prevent spam. |
| LOG(ERROR) << "!!!!!!!!!!!!!!Heap corruption detected!!!!!!!!!!!!!!!!!!!"; |
| } |
| if (obj != nullptr) { |
| // Only do this part for non roots. |
| accounting::CardTable* card_table = heap_->GetCardTable(); |
| accounting::ObjectStack* alloc_stack = heap_->allocation_stack_.get(); |
| accounting::ObjectStack* live_stack = heap_->live_stack_.get(); |
| uint8_t* card_addr = card_table->CardFromAddr(obj); |
| LOG(ERROR) << "Object " << obj << " references dead object " << ref << " at offset " |
| << offset << "\n card value = " << static_cast<int>(*card_addr); |
| if (heap_->IsValidObjectAddress(obj->GetClass())) { |
| LOG(ERROR) << "Obj type " << PrettyTypeOf(obj); |
| } else { |
| LOG(ERROR) << "Object " << obj << " class(" << obj->GetClass() << ") not a heap address"; |
| } |
| |
| // Attempt to find the class inside of the recently freed objects. |
| space::ContinuousSpace* ref_space = heap_->FindContinuousSpaceFromObject(ref, true); |
| if (ref_space != nullptr && ref_space->IsMallocSpace()) { |
| space::MallocSpace* space = ref_space->AsMallocSpace(); |
| mirror::Class* ref_class = space->FindRecentFreedObject(ref); |
| if (ref_class != nullptr) { |
| LOG(ERROR) << "Reference " << ref << " found as a recently freed object with class " |
| << PrettyClass(ref_class); |
| } else { |
| LOG(ERROR) << "Reference " << ref << " not found as a recently freed object"; |
| } |
| } |
| |
| if (ref->GetClass() != nullptr && heap_->IsValidObjectAddress(ref->GetClass()) && |
| ref->GetClass()->IsClass()) { |
| LOG(ERROR) << "Ref type " << PrettyTypeOf(ref); |
| } else { |
| LOG(ERROR) << "Ref " << ref << " class(" << ref->GetClass() |
| << ") is not a valid heap address"; |
| } |
| |
| card_table->CheckAddrIsInCardTable(reinterpret_cast<const uint8_t*>(obj)); |
| void* cover_begin = card_table->AddrFromCard(card_addr); |
| void* cover_end = reinterpret_cast<void*>(reinterpret_cast<size_t>(cover_begin) + |
| accounting::CardTable::kCardSize); |
| LOG(ERROR) << "Card " << reinterpret_cast<void*>(card_addr) << " covers " << cover_begin |
| << "-" << cover_end; |
| accounting::ContinuousSpaceBitmap* bitmap = |
| heap_->GetLiveBitmap()->GetContinuousSpaceBitmap(obj); |
| |
| if (bitmap == nullptr) { |
| LOG(ERROR) << "Object " << obj << " has no bitmap"; |
| if (!VerifyClassClass(obj->GetClass())) { |
| LOG(ERROR) << "Object " << obj << " failed class verification!"; |
| } |
| } else { |
| // Print out how the object is live. |
| if (bitmap->Test(obj)) { |
| LOG(ERROR) << "Object " << obj << " found in live bitmap"; |
| } |
| if (alloc_stack->Contains(const_cast<mirror::Object*>(obj))) { |
| LOG(ERROR) << "Object " << obj << " found in allocation stack"; |
| } |
| if (live_stack->Contains(const_cast<mirror::Object*>(obj))) { |
| LOG(ERROR) << "Object " << obj << " found in live stack"; |
| } |
| if (alloc_stack->Contains(const_cast<mirror::Object*>(ref))) { |
| LOG(ERROR) << "Ref " << ref << " found in allocation stack"; |
| } |
| if (live_stack->Contains(const_cast<mirror::Object*>(ref))) { |
| LOG(ERROR) << "Ref " << ref << " found in live stack"; |
| } |
| // Attempt to see if the card table missed the reference. |
| ScanVisitor scan_visitor; |
| uint8_t* byte_cover_begin = reinterpret_cast<uint8_t*>(card_table->AddrFromCard(card_addr)); |
| card_table->Scan(bitmap, byte_cover_begin, |
| byte_cover_begin + accounting::CardTable::kCardSize, scan_visitor); |
| } |
| |
| // Search to see if any of the roots reference our object. |
| void* arg = const_cast<void*>(reinterpret_cast<const void*>(obj)); |
| Runtime::Current()->VisitRoots(&RootMatchesObjectVisitor, arg); |
| |
| // Search to see if any of the roots reference our reference. |
| arg = const_cast<void*>(reinterpret_cast<const void*>(ref)); |
| Runtime::Current()->VisitRoots(&RootMatchesObjectVisitor, arg); |
| } |
| return false; |
| } |
| |
| Heap* const heap_; |
| Atomic<size_t>* const fail_count_; |
| const bool verify_referent_; |
| }; |
| |
| // Verify all references within an object, for use with HeapBitmap::Visit. |
| class VerifyObjectVisitor { |
| public: |
| explicit VerifyObjectVisitor(Heap* heap, Atomic<size_t>* fail_count, bool verify_referent) |
| : heap_(heap), fail_count_(fail_count), verify_referent_(verify_referent) { |
| } |
| |
| void operator()(mirror::Object* obj) const |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { |
| // Note: we are verifying the references in obj but not obj itself, this is because obj must |
| // be live or else how did we find it in the live bitmap? |
| VerifyReferenceVisitor visitor(heap_, fail_count_, verify_referent_); |
| // The class doesn't count as a reference but we should verify it anyways. |
| obj->VisitReferences<true>(visitor, visitor); |
| } |
| |
| static void VisitCallback(mirror::Object* obj, void* arg) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { |
| VerifyObjectVisitor* visitor = reinterpret_cast<VerifyObjectVisitor*>(arg); |
| visitor->operator()(obj); |
| } |
| |
| size_t GetFailureCount() const { |
| return fail_count_->LoadSequentiallyConsistent(); |
| } |
| |
| private: |
| Heap* const heap_; |
| Atomic<size_t>* const fail_count_; |
| const bool verify_referent_; |
| }; |
| |
| void Heap::PushOnAllocationStackWithInternalGC(Thread* self, mirror::Object** obj) { |
| // Slow path, the allocation stack push back must have already failed. |
| DCHECK(!allocation_stack_->AtomicPushBack(*obj)); |
| do { |
| // TODO: Add handle VerifyObject. |
| StackHandleScope<1> hs(self); |
| HandleWrapper<mirror::Object> wrapper(hs.NewHandleWrapper(obj)); |
| // Push our object into the reserve region of the allocaiton stack. This is only required due |
| // to heap verification requiring that roots are live (either in the live bitmap or in the |
| // allocation stack). |
| CHECK(allocation_stack_->AtomicPushBackIgnoreGrowthLimit(*obj)); |
| CollectGarbageInternal(collector::kGcTypeSticky, kGcCauseForAlloc, false); |
| } while (!allocation_stack_->AtomicPushBack(*obj)); |
| } |
| |
| void Heap::PushOnThreadLocalAllocationStackWithInternalGC(Thread* self, mirror::Object** obj) { |
| // Slow path, the allocation stack push back must have already failed. |
| DCHECK(!self->PushOnThreadLocalAllocationStack(*obj)); |
| mirror::Object** start_address; |
| mirror::Object** end_address; |
| while (!allocation_stack_->AtomicBumpBack(kThreadLocalAllocationStackSize, &start_address, |
| &end_address)) { |
| // TODO: Add handle VerifyObject. |
| StackHandleScope<1> hs(self); |
| HandleWrapper<mirror::Object> wrapper(hs.NewHandleWrapper(obj)); |
| // Push our object into the reserve region of the allocaiton stack. This is only required due |
| // to heap verification requiring that roots are live (either in the live bitmap or in the |
| // allocation stack). |
| CHECK(allocation_stack_->AtomicPushBackIgnoreGrowthLimit(*obj)); |
| // Push into the reserve allocation stack. |
| CollectGarbageInternal(collector::kGcTypeSticky, kGcCauseForAlloc, false); |
| } |
| self->SetThreadLocalAllocationStack(start_address, end_address); |
| // Retry on the new thread-local allocation stack. |
| CHECK(self->PushOnThreadLocalAllocationStack(*obj)); // Must succeed. |
| } |
| |
| // Must do this with mutators suspended since we are directly accessing the allocation stacks. |
| size_t Heap::VerifyHeapReferences(bool verify_referents) { |
| Thread* self = Thread::Current(); |
| Locks::mutator_lock_->AssertExclusiveHeld(self); |
| // Lets sort our allocation stacks so that we can efficiently binary search them. |
| allocation_stack_->Sort(); |
| live_stack_->Sort(); |
| // Since we sorted the allocation stack content, need to revoke all |
| // thread-local allocation stacks. |
| RevokeAllThreadLocalAllocationStacks(self); |
| Atomic<size_t> fail_count_(0); |
| VerifyObjectVisitor visitor(this, &fail_count_, verify_referents); |
| // Verify objects in the allocation stack since these will be objects which were: |
| // 1. Allocated prior to the GC (pre GC verification). |
| // 2. Allocated during the GC (pre sweep GC verification). |
| // We don't want to verify the objects in the live stack since they themselves may be |
| // pointing to dead objects if they are not reachable. |
| VisitObjects(VerifyObjectVisitor::VisitCallback, &visitor); |
| // Verify the roots: |
| Runtime::Current()->VisitRoots(VerifyReferenceVisitor::VerifyRootCallback, &visitor); |
| if (visitor.GetFailureCount() > 0) { |
| // Dump mod-union tables. |
| for (const auto& table_pair : mod_union_tables_) { |
| accounting::ModUnionTable* mod_union_table = table_pair.second; |
| mod_union_table->Dump(LOG(ERROR) << mod_union_table->GetName() << ": "); |
| } |
| // Dump remembered sets. |
| for (const auto& table_pair : remembered_sets_) { |
| accounting::RememberedSet* remembered_set = table_pair.second; |
| remembered_set->Dump(LOG(ERROR) << remembered_set->GetName() << ": "); |
| } |
| DumpSpaces(LOG(ERROR)); |
| } |
| return visitor.GetFailureCount(); |
| } |
| |
| class VerifyReferenceCardVisitor { |
| public: |
| VerifyReferenceCardVisitor(Heap* heap, bool* failed) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, |
| Locks::heap_bitmap_lock_) |
| : heap_(heap), failed_(failed) { |
| } |
| |
| // TODO: Fix lock analysis to not use NO_THREAD_SAFETY_ANALYSIS, requires support for |
| // annotalysis on visitors. |
| void operator()(mirror::Object* obj, MemberOffset offset, bool is_static) const |
| NO_THREAD_SAFETY_ANALYSIS { |
| mirror::Object* ref = obj->GetFieldObject<mirror::Object>(offset); |
| // Filter out class references since changing an object's class does not mark the card as dirty. |
| // Also handles large objects, since the only reference they hold is a class reference. |
| if (ref != nullptr && !ref->IsClass()) { |
| accounting::CardTable* card_table = heap_->GetCardTable(); |
| // If the object is not dirty and it is referencing something in the live stack other than |
| // class, then it must be on a dirty card. |
| if (!card_table->AddrIsInCardTable(obj)) { |
| LOG(ERROR) << "Object " << obj << " is not in the address range of the card table"; |
| *failed_ = true; |
| } else if (!card_table->IsDirty(obj)) { |
| // TODO: Check mod-union tables. |
| // Card should be either kCardDirty if it got re-dirtied after we aged it, or |
| // kCardDirty - 1 if it didnt get touched since we aged it. |
| accounting::ObjectStack* live_stack = heap_->live_stack_.get(); |
| if (live_stack->ContainsSorted(ref)) { |
| if (live_stack->ContainsSorted(obj)) { |
| LOG(ERROR) << "Object " << obj << " found in live stack"; |
| } |
| if (heap_->GetLiveBitmap()->Test(obj)) { |
| LOG(ERROR) << "Object " << obj << " found in live bitmap"; |
| } |
| LOG(ERROR) << "Object " << obj << " " << PrettyTypeOf(obj) |
| << " references " << ref << " " << PrettyTypeOf(ref) << " in live stack"; |
| |
| // Print which field of the object is dead. |
| if (!obj->IsObjectArray()) { |
| mirror::Class* klass = is_static ? obj->AsClass() : obj->GetClass(); |
| CHECK(klass != NULL); |
| mirror::ObjectArray<mirror::ArtField>* fields = is_static ? klass->GetSFields() |
| : klass->GetIFields(); |
| CHECK(fields != NULL); |
| for (int32_t i = 0; i < fields->GetLength(); ++i) { |
| mirror::ArtField* cur = fields->Get(i); |
| if (cur->GetOffset().Int32Value() == offset.Int32Value()) { |
| LOG(ERROR) << (is_static ? "Static " : "") << "field in the live stack is " |
| << PrettyField(cur); |
| break; |
| } |
| } |
| } else { |
| mirror::ObjectArray<mirror::Object>* object_array = |
| obj->AsObjectArray<mirror::Object>(); |
| for (int32_t i = 0; i < object_array->GetLength(); ++i) { |
| if (object_array->Get(i) == ref) { |
| LOG(ERROR) << (is_static ? "Static " : "") << "obj[" << i << "] = ref"; |
| } |
| } |
| } |
| |
| *failed_ = true; |
| } |
| } |
| } |
| } |
| |
| private: |
| Heap* const heap_; |
| bool* const failed_; |
| }; |
| |
| class VerifyLiveStackReferences { |
| public: |
| explicit VerifyLiveStackReferences(Heap* heap) |
| : heap_(heap), |
| failed_(false) {} |
| |
| void operator()(mirror::Object* obj) const |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { |
| VerifyReferenceCardVisitor visitor(heap_, const_cast<bool*>(&failed_)); |
| obj->VisitReferences<true>(visitor, VoidFunctor()); |
| } |
| |
| bool Failed() const { |
| return failed_; |
| } |
| |
| private: |
| Heap* const heap_; |
| bool failed_; |
| }; |
| |
| bool Heap::VerifyMissingCardMarks() { |
| Thread* self = Thread::Current(); |
| Locks::mutator_lock_->AssertExclusiveHeld(self); |
| // We need to sort the live stack since we binary search it. |
| live_stack_->Sort(); |
| // Since we sorted the allocation stack content, need to revoke all |
| // thread-local allocation stacks. |
| RevokeAllThreadLocalAllocationStacks(self); |
| VerifyLiveStackReferences visitor(this); |
| GetLiveBitmap()->Visit(visitor); |
| // We can verify objects in the live stack since none of these should reference dead objects. |
| for (mirror::Object** it = live_stack_->Begin(); it != live_stack_->End(); ++it) { |
| if (!kUseThreadLocalAllocationStack || *it != nullptr) { |
| visitor(*it); |
| } |
| } |
| return !visitor.Failed(); |
| } |
| |
| void Heap::SwapStacks(Thread* self) { |
| UNUSED(self); |
| if (kUseThreadLocalAllocationStack) { |
| live_stack_->AssertAllZero(); |
| } |
| allocation_stack_.swap(live_stack_); |
| } |
| |
| void Heap::RevokeAllThreadLocalAllocationStacks(Thread* self) { |
| // This must be called only during the pause. |
| CHECK(Locks::mutator_lock_->IsExclusiveHeld(self)); |
| MutexLock mu(self, *Locks::runtime_shutdown_lock_); |
| MutexLock mu2(self, *Locks::thread_list_lock_); |
| std::list<Thread*> thread_list = Runtime::Current()->GetThreadList()->GetList(); |
| for (Thread* t : thread_list) { |
| t->RevokeThreadLocalAllocationStack(); |
| } |
| } |
| |
| void Heap::AssertThreadLocalBuffersAreRevoked(Thread* thread) { |
| if (kIsDebugBuild) { |
| if (rosalloc_space_ != nullptr) { |
| rosalloc_space_->AssertThreadLocalBuffersAreRevoked(thread); |
| } |
| if (bump_pointer_space_ != nullptr) { |
| bump_pointer_space_->AssertThreadLocalBuffersAreRevoked(thread); |
| } |
| } |
| } |
| |
| void Heap::AssertAllBumpPointerSpaceThreadLocalBuffersAreRevoked() { |
| if (kIsDebugBuild) { |
| if (bump_pointer_space_ != nullptr) { |
| bump_pointer_space_->AssertAllThreadLocalBuffersAreRevoked(); |
| } |
| } |
| } |
| |
| accounting::ModUnionTable* Heap::FindModUnionTableFromSpace(space::Space* space) { |
| auto it = mod_union_tables_.find(space); |
| if (it == mod_union_tables_.end()) { |
| return nullptr; |
| } |
| return it->second; |
| } |
| |
| accounting::RememberedSet* Heap::FindRememberedSetFromSpace(space::Space* space) { |
| auto it = remembered_sets_.find(space); |
| if (it == remembered_sets_.end()) { |
| return nullptr; |
| } |
| return it->second; |
| } |
| |
| void Heap::ProcessCards(TimingLogger* timings, bool use_rem_sets) { |
| TimingLogger::ScopedTiming t(__FUNCTION__, timings); |
| // Clear cards and keep track of cards cleared in the mod-union table. |
| for (const auto& space : continuous_spaces_) { |
| accounting::ModUnionTable* table = FindModUnionTableFromSpace(space); |
| accounting::RememberedSet* rem_set = FindRememberedSetFromSpace(space); |
| if (table != nullptr) { |
| const char* name = space->IsZygoteSpace() ? "ZygoteModUnionClearCards" : |
| "ImageModUnionClearCards"; |
| TimingLogger::ScopedTiming t(name, timings); |
| table->ClearCards(); |
| } else if (use_rem_sets && rem_set != nullptr) { |
| DCHECK(collector::SemiSpace::kUseRememberedSet && collector_type_ == kCollectorTypeGSS) |
| << static_cast<int>(collector_type_); |
| TimingLogger::ScopedTiming t("AllocSpaceRemSetClearCards", timings); |
| rem_set->ClearCards(); |
| } else if (space->GetType() != space::kSpaceTypeBumpPointerSpace) { |
| TimingLogger::ScopedTiming t("AllocSpaceClearCards", timings); |
| // No mod union table for the AllocSpace. Age the cards so that the GC knows that these cards |
| // were dirty before the GC started. |
| // TODO: Need to use atomic for the case where aged(cleaning thread) -> dirty(other thread) |
| // -> clean(cleaning thread). |
| // The races are we either end up with: Aged card, unaged card. Since we have the checkpoint |
| // roots and then we scan / update mod union tables after. We will always scan either card. |
| // If we end up with the non aged card, we scan it it in the pause. |
| card_table_->ModifyCardsAtomic(space->Begin(), space->End(), AgeCardVisitor(), |
| VoidFunctor()); |
| } |
| } |
| } |
| |
| static void IdentityMarkHeapReferenceCallback(mirror::HeapReference<mirror::Object>*, void*) { |
| } |
| |
| void Heap::PreGcVerificationPaused(collector::GarbageCollector* gc) { |
| Thread* const self = Thread::Current(); |
| TimingLogger* const timings = current_gc_iteration_.GetTimings(); |
| TimingLogger::ScopedTiming t(__FUNCTION__, timings); |
| if (verify_pre_gc_heap_) { |
| TimingLogger::ScopedTiming t("(Paused)PreGcVerifyHeapReferences", timings); |
| ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_); |
| size_t failures = VerifyHeapReferences(); |
| if (failures > 0) { |
| LOG(FATAL) << "Pre " << gc->GetName() << " heap verification failed with " << failures |
| << " failures"; |
| } |
| } |
| // Check that all objects which reference things in the live stack are on dirty cards. |
| if (verify_missing_card_marks_) { |
| TimingLogger::ScopedTiming t("(Paused)PreGcVerifyMissingCardMarks", timings); |
| ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_); |
| SwapStacks(self); |
| // Sort the live stack so that we can quickly binary search it later. |
| CHECK(VerifyMissingCardMarks()) << "Pre " << gc->GetName() |
| << " missing card mark verification failed\n" << DumpSpaces(); |
| SwapStacks(self); |
| } |
| if (verify_mod_union_table_) { |
| TimingLogger::ScopedTiming t("(Paused)PreGcVerifyModUnionTables", timings); |
| ReaderMutexLock reader_lock(self, *Locks::heap_bitmap_lock_); |
| for (const auto& table_pair : mod_union_tables_) { |
| accounting::ModUnionTable* mod_union_table = table_pair.second; |
| mod_union_table->UpdateAndMarkReferences(IdentityMarkHeapReferenceCallback, nullptr); |
| mod_union_table->Verify(); |
| } |
| } |
| } |
| |
| void Heap::PreGcVerification(collector::GarbageCollector* gc) { |
| if (verify_pre_gc_heap_ || verify_missing_card_marks_ || verify_mod_union_table_) { |
| collector::GarbageCollector::ScopedPause pause(gc); |
| PreGcVerificationPaused(gc); |
| } |
| } |
| |
| void Heap::PrePauseRosAllocVerification(collector::GarbageCollector* gc) { |
| UNUSED(gc); |
| // TODO: Add a new runtime option for this? |
| if (verify_pre_gc_rosalloc_) { |
| RosAllocVerification(current_gc_iteration_.GetTimings(), "PreGcRosAllocVerification"); |
| } |
| } |
| |
| void Heap::PreSweepingGcVerification(collector::GarbageCollector* gc) { |
| Thread* const self = Thread::Current(); |
| TimingLogger* const timings = current_gc_iteration_.GetTimings(); |
| TimingLogger::ScopedTiming t(__FUNCTION__, timings); |
| // Called before sweeping occurs since we want to make sure we are not going so reclaim any |
| // reachable objects. |
| if (verify_pre_sweeping_heap_) { |
| TimingLogger::ScopedTiming t("(Paused)PostSweepingVerifyHeapReferences", timings); |
| CHECK_NE(self->GetState(), kRunnable); |
| WriterMutexLock mu(self, *Locks::heap_bitmap_lock_); |
| // Swapping bound bitmaps does nothing. |
| gc->SwapBitmaps(); |
| // Pass in false since concurrent reference processing can mean that the reference referents |
| // may point to dead objects at the point which PreSweepingGcVerification is called. |
| size_t failures = VerifyHeapReferences(false); |
| if (failures > 0) { |
| LOG(FATAL) << "Pre sweeping " << gc->GetName() << " GC verification failed with " << failures |
| << " failures"; |
| } |
| gc->SwapBitmaps(); |
| } |
| if (verify_pre_sweeping_rosalloc_) { |
| RosAllocVerification(timings, "PreSweepingRosAllocVerification"); |
| } |
| } |
| |
| void Heap::PostGcVerificationPaused(collector::GarbageCollector* gc) { |
| // Only pause if we have to do some verification. |
| Thread* const self = Thread::Current(); |
| TimingLogger* const timings = GetCurrentGcIteration()->GetTimings(); |
| TimingLogger::ScopedTiming t(__FUNCTION__, timings); |
| if (verify_system_weaks_) { |
| ReaderMutexLock mu2(self, *Locks::heap_bitmap_lock_); |
| collector::MarkSweep* mark_sweep = down_cast<collector::MarkSweep*>(gc); |
| mark_sweep->VerifySystemWeaks(); |
| } |
| if (verify_post_gc_rosalloc_) { |
| RosAllocVerification(timings, "(Paused)PostGcRosAllocVerification"); |
| } |
| if (verify_post_gc_heap_) { |
| TimingLogger::ScopedTiming t("(Paused)PostGcVerifyHeapReferences", timings); |
| ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_); |
| size_t failures = VerifyHeapReferences(); |
| if (failures > 0) { |
| LOG(FATAL) << "Pre " << gc->GetName() << " heap verification failed with " << failures |
| << " failures"; |
| } |
| } |
| } |
| |
| void Heap::PostGcVerification(collector::GarbageCollector* gc) { |
| if (verify_system_weaks_ || verify_post_gc_rosalloc_ || verify_post_gc_heap_) { |
| collector::GarbageCollector::ScopedPause pause(gc); |
| PostGcVerificationPaused(gc); |
| } |
| } |
| |
| void Heap::RosAllocVerification(TimingLogger* timings, const char* name) { |
| TimingLogger::ScopedTiming t(name, timings); |
| for (const auto& space : continuous_spaces_) { |
| if (space->IsRosAllocSpace()) { |
| VLOG(heap) << name << " : " << space->GetName(); |
| space->AsRosAllocSpace()->Verify(); |
| } |
| } |
| } |
| |
| collector::GcType Heap::WaitForGcToComplete(GcCause cause, Thread* self) { |
| ScopedThreadStateChange tsc(self, kWaitingForGcToComplete); |
| MutexLock mu(self, *gc_complete_lock_); |
| return WaitForGcToCompleteLocked(cause, self); |
| } |
| |
| collector::GcType Heap::WaitForGcToCompleteLocked(GcCause cause, Thread* self) { |
| collector::GcType last_gc_type = collector::kGcTypeNone; |
| uint64_t wait_start = NanoTime(); |
| while (collector_type_running_ != kCollectorTypeNone) { |
| ATRACE_BEGIN("GC: Wait For Completion"); |
| // We must wait, change thread state then sleep on gc_complete_cond_; |
| gc_complete_cond_->Wait(self); |
| last_gc_type = last_gc_type_; |
| ATRACE_END(); |
| } |
| uint64_t wait_time = NanoTime() - wait_start; |
| total_wait_time_ += wait_time; |
| if (wait_time > long_pause_log_threshold_) { |
| LOG(INFO) << "WaitForGcToComplete blocked for " << PrettyDuration(wait_time) |
| << " for cause " << cause; |
| } |
| return last_gc_type; |
| } |
| |
| void Heap::DumpForSigQuit(std::ostream& os) { |
| os << "Heap: " << GetPercentFree() << "% free, " << PrettySize(GetBytesAllocated()) << "/" |
| << PrettySize(GetTotalMemory()) << "; " << GetObjectsAllocated() << " objects\n"; |
| DumpGcPerformanceInfo(os); |
| } |
| |
| size_t Heap::GetPercentFree() { |
| return static_cast<size_t>(100.0f * static_cast<float>(GetFreeMemory()) / max_allowed_footprint_); |
| } |
| |
| void Heap::SetIdealFootprint(size_t max_allowed_footprint) { |
| if (max_allowed_footprint > GetMaxMemory()) { |
| VLOG(gc) << "Clamp target GC heap from " << PrettySize(max_allowed_footprint) << " to " |
| << PrettySize(GetMaxMemory()); |
| max_allowed_footprint = GetMaxMemory(); |
| } |
| max_allowed_footprint_ = max_allowed_footprint; |
| } |
| |
| bool Heap::IsMovableObject(const mirror::Object* obj) const { |
| if (kMovingCollector) { |
| space::Space* space = FindContinuousSpaceFromObject(obj, true); |
| if (space != nullptr) { |
| // TODO: Check large object? |
| return space->CanMoveObjects(); |
| } |
| } |
| return false; |
| } |
| |
| void Heap::UpdateMaxNativeFootprint() { |
| size_t native_size = native_bytes_allocated_.LoadRelaxed(); |
| // TODO: Tune the native heap utilization to be a value other than the java heap utilization. |
| size_t target_size = native_size / GetTargetHeapUtilization(); |
| if (target_size > native_size + max_free_) { |
| target_size = native_size + max_free_; |
| } else if (target_size < native_size + min_free_) { |
| target_size = native_size + min_free_; |
| } |
| native_footprint_gc_watermark_ = std::min(growth_limit_, target_size); |
| } |
| |
| collector::GarbageCollector* Heap::FindCollectorByGcType(collector::GcType gc_type) { |
| for (const auto& collector : garbage_collectors_) { |
| if (collector->GetCollectorType() == collector_type_ && |
| collector->GetGcType() == gc_type) { |
| return collector; |
| } |
| } |
| return nullptr; |
| } |
| |
| double Heap::HeapGrowthMultiplier() const { |
| // If we don't care about pause times we are background, so return 1.0. |
| if (!CareAboutPauseTimes() || IsLowMemoryMode()) { |
| return 1.0; |
| } |
| return foreground_heap_growth_multiplier_; |
| } |
| |
| void Heap::GrowForUtilization(collector::GarbageCollector* collector_ran) { |
| // We know what our utilization is at this moment. |
| // This doesn't actually resize any memory. It just lets the heap grow more when necessary. |
| const uint64_t bytes_allocated = GetBytesAllocated(); |
| last_gc_size_ = bytes_allocated; |
| last_gc_time_ns_ = NanoTime(); |
| uint64_t target_size; |
| collector::GcType gc_type = collector_ran->GetGcType(); |
| if (gc_type != collector::kGcTypeSticky) { |
| // Grow the heap for non sticky GC. |
| const float multiplier = HeapGrowthMultiplier(); // Use the multiplier to grow more for |
| // foreground. |
| intptr_t delta = bytes_allocated / GetTargetHeapUtilization() - bytes_allocated; |
| CHECK_GE(delta, 0); |
| target_size = bytes_allocated + delta * multiplier; |
| target_size = std::min(target_size, |
| bytes_allocated + static_cast<uint64_t>(max_free_ * multiplier)); |
| target_size = std::max(target_size, |
| bytes_allocated + static_cast<uint64_t>(min_free_ * multiplier)); |
| native_need_to_run_finalization_ = true; |
| next_gc_type_ = collector::kGcTypeSticky; |
| } else { |
| collector::GcType non_sticky_gc_type = |
| HasZygoteSpace() ? collector::kGcTypePartial : collector::kGcTypeFull; |
| // Find what the next non sticky collector will be. |
| collector::GarbageCollector* non_sticky_collector = FindCollectorByGcType(non_sticky_gc_type); |
| // If the throughput of the current sticky GC >= throughput of the non sticky collector, then |
| // do another sticky collection next. |
| // We also check that the bytes allocated aren't over the footprint limit in order to prevent a |
| // pathological case where dead objects which aren't reclaimed by sticky could get accumulated |
| // if the sticky GC throughput always remained >= the full/partial throughput. |
| if (current_gc_iteration_.GetEstimatedThroughput() * kStickyGcThroughputAdjustment >= |
| non_sticky_collector->GetEstimatedMeanThroughput() && |
| non_sticky_collector->NumberOfIterations() > 0 && |
| bytes_allocated <= max_allowed_footprint_) { |
| next_gc_type_ = collector::kGcTypeSticky; |
| } else { |
| next_gc_type_ = non_sticky_gc_type; |
| } |
| // If we have freed enough memory, shrink the heap back down. |
| if (bytes_allocated + max_free_ < max_allowed_footprint_) { |
| target_size = bytes_allocated + max_free_; |
| } else { |
| target_size = std::max(bytes_allocated, static_cast<uint64_t>(max_allowed_footprint_)); |
| } |
| } |
| if (!ignore_max_footprint_) { |
| SetIdealFootprint(target_size); |
| if (IsGcConcurrent()) { |
| // Calculate when to perform the next ConcurrentGC. |
| // Calculate the estimated GC duration. |
| const double gc_duration_seconds = NsToMs(current_gc_iteration_.GetDurationNs()) / 1000.0; |
| // Estimate how many remaining bytes we will have when we need to start the next GC. |
| size_t remaining_bytes = allocation_rate_ * gc_duration_seconds; |
| remaining_bytes = std::min(remaining_bytes, kMaxConcurrentRemainingBytes); |
| remaining_bytes = std::max(remaining_bytes, kMinConcurrentRemainingBytes); |
| if (UNLIKELY(remaining_bytes > max_allowed_footprint_)) { |
| // A never going to happen situation that from the estimated allocation rate we will exceed |
| // the applications entire footprint with the given estimated allocation rate. Schedule |
| // another GC nearly straight away. |
| remaining_bytes = kMinConcurrentRemainingBytes; |
| } |
| DCHECK_LE(remaining_bytes, max_allowed_footprint_); |
| DCHECK_LE(max_allowed_footprint_, GetMaxMemory()); |
| // Start a concurrent GC when we get close to the estimated remaining bytes. When the |
| // allocation rate is very high, remaining_bytes could tell us that we should start a GC |
| // right away. |
| concurrent_start_bytes_ = std::max(max_allowed_footprint_ - remaining_bytes, |
| static_cast<size_t>(bytes_allocated)); |
| } |
| } |
| } |
| |
| void Heap::ClearGrowthLimit() { |
| growth_limit_ = capacity_; |
| non_moving_space_->ClearGrowthLimit(); |
| } |
| |
| void Heap::AddFinalizerReference(Thread* self, mirror::Object** object) { |
| ScopedObjectAccess soa(self); |
| ScopedLocalRef<jobject> arg(self->GetJniEnv(), soa.AddLocalReference<jobject>(*object)); |
| jvalue args[1]; |
| args[0].l = arg.get(); |
| InvokeWithJValues(soa, nullptr, WellKnownClasses::java_lang_ref_FinalizerReference_add, args); |
| // Restore object in case it gets moved. |
| *object = soa.Decode<mirror::Object*>(arg.get()); |
| } |
| |
| void Heap::RequestConcurrentGCAndSaveObject(Thread* self, mirror::Object** obj) { |
| StackHandleScope<1> hs(self); |
| HandleWrapper<mirror::Object> wrapper(hs.NewHandleWrapper(obj)); |
| RequestConcurrentGC(self); |
| } |
| |
| void Heap::RequestConcurrentGC(Thread* self) { |
| // Make sure that we can do a concurrent GC. |
| Runtime* runtime = Runtime::Current(); |
| if (runtime == nullptr || !runtime->IsFinishedStarting() || runtime->IsShuttingDown(self) || |
| self->IsHandlingStackOverflow()) { |
| return; |
| } |
| JNIEnv* env = self->GetJniEnv(); |
| DCHECK(WellKnownClasses::java_lang_Daemons != nullptr); |
| DCHECK(WellKnownClasses::java_lang_Daemons_requestGC != nullptr); |
| env->CallStaticVoidMethod(WellKnownClasses::java_lang_Daemons, |
| WellKnownClasses::java_lang_Daemons_requestGC); |
| CHECK(!env->ExceptionCheck()); |
| } |
| |
| void Heap::ConcurrentGC(Thread* self) { |
| if (Runtime::Current()->IsShuttingDown(self)) { |
| return; |
| } |
| // Wait for any GCs currently running to finish. |
| if (WaitForGcToComplete(kGcCauseBackground, self) == collector::kGcTypeNone) { |
| // If the we can't run the GC type we wanted to run, find the next appropriate one and try that |
| // instead. E.g. can't do partial, so do full instead. |
| if (CollectGarbageInternal(next_gc_type_, kGcCauseBackground, false) == |
| collector::kGcTypeNone) { |
| for (collector::GcType gc_type : gc_plan_) { |
| // Attempt to run the collector, if we succeed, we are done. |
| if (gc_type > next_gc_type_ && |
| CollectGarbageInternal(gc_type, kGcCauseBackground, false) != collector::kGcTypeNone) { |
| break; |
| } |
| } |
| } |
| } |
| } |
| |
| void Heap::RequestCollectorTransition(CollectorType desired_collector_type, uint64_t delta_time) { |
| Thread* self = Thread::Current(); |
| { |
| MutexLock mu(self, *heap_trim_request_lock_); |
| if (desired_collector_type_ == desired_collector_type) { |
| return; |
| } |
| heap_transition_or_trim_target_time_ = |
| std::max(heap_transition_or_trim_target_time_, NanoTime() + delta_time); |
| desired_collector_type_ = desired_collector_type; |
| } |
| SignalHeapTrimDaemon(self); |
| } |
| |
| void Heap::RequestHeapTrim() { |
| // GC completed and now we must decide whether to request a heap trim (advising pages back to the |
| // kernel) or not. Issuing a request will also cause trimming of the libc heap. As a trim scans |
| // a space it will hold its lock and can become a cause of jank. |
| // Note, the large object space self trims and the Zygote space was trimmed and unchanging since |
| // forking. |
| |
| // We don't have a good measure of how worthwhile a trim might be. We can't use the live bitmap |
| // because that only marks object heads, so a large array looks like lots of empty space. We |
| // don't just call dlmalloc all the time, because the cost of an _attempted_ trim is proportional |
| // to utilization (which is probably inversely proportional to how much benefit we can expect). |
| // We could try mincore(2) but that's only a measure of how many pages we haven't given away, |
| // not how much use we're making of those pages. |
| |
| Thread* self = Thread::Current(); |
| Runtime* runtime = Runtime::Current(); |
| if (runtime == nullptr || !runtime->IsFinishedStarting() || runtime->IsShuttingDown(self) || |
| runtime->IsZygote()) { |
| // Ignore the request if we are the zygote to prevent app launching lag due to sleep in heap |
| // trimmer daemon. b/17310019 |
| // Heap trimming isn't supported without a Java runtime or Daemons (such as at dex2oat time) |
| // Also: we do not wish to start a heap trim if the runtime is shutting down (a racy check |
| // as we don't hold the lock while requesting the trim). |
| return; |
| } |
| { |
| MutexLock mu(self, *heap_trim_request_lock_); |
| if (last_trim_time_ + kHeapTrimWait >= NanoTime()) { |
| // We have done a heap trim in the last kHeapTrimWait nanosecs, don't request another one |
| // just yet. |
| return; |
| } |
| heap_trim_request_pending_ = true; |
| uint64_t current_time = NanoTime(); |
| if (heap_transition_or_trim_target_time_ < current_time) { |
| heap_transition_or_trim_target_time_ = current_time + kHeapTrimWait; |
| } |
| } |
| // Notify the daemon thread which will actually do the heap trim. |
| SignalHeapTrimDaemon(self); |
| } |
| |
| void Heap::SignalHeapTrimDaemon(Thread* self) { |
| JNIEnv* env = self->GetJniEnv(); |
| DCHECK(WellKnownClasses::java_lang_Daemons != nullptr); |
| DCHECK(WellKnownClasses::java_lang_Daemons_requestHeapTrim != nullptr); |
| env->CallStaticVoidMethod(WellKnownClasses::java_lang_Daemons, |
| WellKnownClasses::java_lang_Daemons_requestHeapTrim); |
| CHECK(!env->ExceptionCheck()); |
| } |
| |
| void Heap::RevokeThreadLocalBuffers(Thread* thread) { |
| if (rosalloc_space_ != nullptr) { |
| rosalloc_space_->RevokeThreadLocalBuffers(thread); |
| } |
| if (bump_pointer_space_ != nullptr) { |
| bump_pointer_space_->RevokeThreadLocalBuffers(thread); |
| } |
| } |
| |
| void Heap::RevokeRosAllocThreadLocalBuffers(Thread* thread) { |
| if (rosalloc_space_ != nullptr) { |
| rosalloc_space_->RevokeThreadLocalBuffers(thread); |
| } |
| } |
| |
| void Heap::RevokeAllThreadLocalBuffers() { |
| if (rosalloc_space_ != nullptr) { |
| rosalloc_space_->RevokeAllThreadLocalBuffers(); |
| } |
| if (bump_pointer_space_ != nullptr) { |
| bump_pointer_space_->RevokeAllThreadLocalBuffers(); |
| } |
| } |
| |
| bool Heap::IsGCRequestPending() const { |
| return concurrent_start_bytes_ != std::numeric_limits<size_t>::max(); |
| } |
| |
| void Heap::RunFinalization(JNIEnv* env) { |
| // Can't do this in WellKnownClasses::Init since System is not properly set up at that point. |
| if (WellKnownClasses::java_lang_System_runFinalization == nullptr) { |
| CHECK(WellKnownClasses::java_lang_System != nullptr); |
| WellKnownClasses::java_lang_System_runFinalization = |
| CacheMethod(env, WellKnownClasses::java_lang_System, true, "runFinalization", "()V"); |
| CHECK(WellKnownClasses::java_lang_System_runFinalization != nullptr); |
| } |
| env->CallStaticVoidMethod(WellKnownClasses::java_lang_System, |
| WellKnownClasses::java_lang_System_runFinalization); |
| } |
| |
| void Heap::RegisterNativeAllocation(JNIEnv* env, size_t bytes) { |
| Thread* self = ThreadForEnv(env); |
| if (native_need_to_run_finalization_) { |
| RunFinalization(env); |
| UpdateMaxNativeFootprint(); |
| native_need_to_run_finalization_ = false; |
| } |
| // Total number of native bytes allocated. |
| size_t new_native_bytes_allocated = native_bytes_allocated_.FetchAndAddSequentiallyConsistent(bytes); |
| new_native_bytes_allocated += bytes; |
| if (new_native_bytes_allocated > native_footprint_gc_watermark_) { |
| collector::GcType gc_type = HasZygoteSpace() ? collector::kGcTypePartial : |
| collector::kGcTypeFull; |
| |
| // The second watermark is higher than the gc watermark. If you hit this it means you are |
| // allocating native objects faster than the GC can keep up with. |
| if (new_native_bytes_allocated > growth_limit_) { |
| if (WaitForGcToComplete(kGcCauseForNativeAlloc, self) != collector::kGcTypeNone) { |
| // Just finished a GC, attempt to run finalizers. |
| RunFinalization(env); |
| CHECK(!env->ExceptionCheck()); |
| } |
| // If we still are over the watermark, attempt a GC for alloc and run finalizers. |
| if (new_native_bytes_allocated > growth_limit_) { |
| CollectGarbageInternal(gc_type, kGcCauseForNativeAlloc, false); |
| RunFinalization(env); |
| native_need_to_run_finalization_ = false; |
| CHECK(!env->ExceptionCheck()); |
| } |
| // We have just run finalizers, update the native watermark since it is very likely that |
| // finalizers released native managed allocations. |
| UpdateMaxNativeFootprint(); |
| } else if (!IsGCRequestPending()) { |
| if (IsGcConcurrent()) { |
| RequestConcurrentGC(self); |
| } else { |
| CollectGarbageInternal(gc_type, kGcCauseForNativeAlloc, false); |
| } |
| } |
| } |
| } |
| |
| void Heap::RegisterNativeFree(JNIEnv* env, size_t bytes) { |
| size_t expected_size; |
| do { |
| expected_size = native_bytes_allocated_.LoadRelaxed(); |
| if (UNLIKELY(bytes > expected_size)) { |
| ScopedObjectAccess soa(env); |
| env->ThrowNew(WellKnownClasses::java_lang_RuntimeException, |
| StringPrintf("Attempted to free %zd native bytes with only %zd native bytes " |
| "registered as allocated", bytes, expected_size).c_str()); |
| break; |
| } |
| } while (!native_bytes_allocated_.CompareExchangeWeakRelaxed(expected_size, |
| expected_size - bytes)); |
| } |
| |
| size_t Heap::GetTotalMemory() const { |
| return std::max(max_allowed_footprint_, GetBytesAllocated()); |
| } |
| |
| void Heap::AddModUnionTable(accounting::ModUnionTable* mod_union_table) { |
| DCHECK(mod_union_table != nullptr); |
| mod_union_tables_.Put(mod_union_table->GetSpace(), mod_union_table); |
| } |
| |
| void Heap::CheckPreconditionsForAllocObject(mirror::Class* c, size_t byte_count) { |
| CHECK(c == NULL || (c->IsClassClass() && byte_count >= sizeof(mirror::Class)) || |
| (c->IsVariableSize() || c->GetObjectSize() == byte_count)); |
| CHECK_GE(byte_count, sizeof(mirror::Object)); |
| } |
| |
| void Heap::AddRememberedSet(accounting::RememberedSet* remembered_set) { |
| CHECK(remembered_set != nullptr); |
| space::Space* space = remembered_set->GetSpace(); |
| CHECK(space != nullptr); |
| CHECK(remembered_sets_.find(space) == remembered_sets_.end()) << space; |
| remembered_sets_.Put(space, remembered_set); |
| CHECK(remembered_sets_.find(space) != remembered_sets_.end()) << space; |
| } |
| |
| void Heap::RemoveRememberedSet(space::Space* space) { |
| CHECK(space != nullptr); |
| auto it = remembered_sets_.find(space); |
| CHECK(it != remembered_sets_.end()); |
| delete it->second; |
| remembered_sets_.erase(it); |
| CHECK(remembered_sets_.find(space) == remembered_sets_.end()); |
| } |
| |
| void Heap::ClearMarkedObjects() { |
| // Clear all of the spaces' mark bitmaps. |
| for (const auto& space : GetContinuousSpaces()) { |
| accounting::ContinuousSpaceBitmap* mark_bitmap = space->GetMarkBitmap(); |
| if (space->GetLiveBitmap() != mark_bitmap) { |
| mark_bitmap->Clear(); |
| } |
| } |
| // Clear the marked objects in the discontinous space object sets. |
| for (const auto& space : GetDiscontinuousSpaces()) { |
| space->GetMarkBitmap()->Clear(); |
| } |
| } |
| |
| } // namespace gc |
| } // namespace art |