Quelle  rosalloc_space.h

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef ART_RUNTIME_GC_SPACE_ROSALLOC_SPACE_H_
#define ART_RUNTIME_GC_SPACE_ROSALLOC_SPACE_H_

#include "gc/allocator/rosalloc.h"
#include "malloc_space.h"
#include "space.h"

namespace art HIDDEN {
namespace gc {

namespace collector {
class MarkSweep;
}  // namespace collector

namespace space {

// An alloc space implemented using a runs-of-slots memory allocator. Not final as may be
// overridden by a MemoryToolMallocSpace.
class RosAllocSpace : public MallocSpace {
 public:
  // Create a RosAllocSpace with the requested sizes. The requested
  // base address is not guaranteed to be granted, if it is required,
  // the caller should call Begin on the returned space to confirm the
  // request was granted.
  static RosAllocSpace* Create(const std::string& name,
                               size_t initial_size,
                               size_t growth_limit,
                               size_t capacity,
                               bool low_memory_mode,
                               bool can_move_objects);
  static RosAllocSpace* CreateFromMemMap(MemMap&& mem_map,
                                         const std::string& name,
                                         size_t starting_size,
                                         size_t initial_size,
                                         size_t growth_limit,
                                         size_t capacity,
                                         bool low_memory_mode,
                                         bool can_move_objects);

  mirror::Object* AllocWithGrowth(Thread* self, size_t num_bytes, size_t* bytes_allocated,
                                  size_t* usable_size, size_t* bytes_tl_bulk_allocated)
      override REQUIRES(!lock_);
  mirror::Object* Alloc(Thread* self, size_t num_bytes, size_t* bytes_allocated,
                        size_t* usable_size, size_t* bytes_tl_bulk_allocated) override {
    return AllocNonvirtual(self, num_bytes, bytes_allocated, usable_size,
                           bytes_tl_bulk_allocated);
  }
  mirror::Object* AllocThreadUnsafe(Thread* self, size_t num_bytes, size_t* bytes_allocated,
                                    size_t* usable_size, size_t* bytes_tl_bulk_allocated)
      override REQUIRES(Locks::mutator_lock_) {
    return AllocNonvirtualThreadUnsafe(self, num_bytes, bytes_allocated, usable_size,
                                       bytes_tl_bulk_allocated);
  }
  size_t AllocationSize(mirror::Object* obj, size_t* usable_size) override {
    return AllocationSizeNonvirtual<true>(obj, usable_size);
  }
  size_t Free(Thread* self, mirror::Object* ptr) override
      REQUIRES_SHARED(Locks::mutator_lock_);
  size_t FreeList(Thread* self, size_t num_ptrs, mirror::Object** ptrs) override
      REQUIRES_SHARED(Locks::mutator_lock_);

  mirror::Object* AllocNonvirtual(Thread* self, size_t num_bytes, size_t* bytes_allocated,
                                  size_t* usable_size, size_t* bytes_tl_bulk_allocated) {
    // RosAlloc zeroes memory internally.
    return AllocCommon(self, num_bytes, bytes_allocated, usable_size,
                       bytes_tl_bulk_allocated);
  }
  mirror::Object* AllocNonvirtualThreadUnsafe(Thread* self, size_t num_bytes,
                                              size_t* bytes_allocated, size_t* usable_size,
                                              size_t* bytes_tl_bulk_allocated) {
    // RosAlloc zeroes memory internally. Pass in false for thread unsafe.
    return AllocCommon<false>(self, num_bytes, bytes_allocated, usable_size,
                              bytes_tl_bulk_allocated);
  }

  // Returns true if the given allocation request can be allocated in
  // an existing thread local run without allocating a new run.
  ALWAYS_INLINE bool CanAllocThreadLocal(Thread* self, size_t num_bytes);
  // Allocate the given allocation request in an existing thread local
  // run without allocating a new run.
  ALWAYS_INLINE mirror::Object* AllocThreadLocal(Thread* self, size_t num_bytes,
                                                 size_t* bytes_allocated);
  size_t MaxBytesBulkAllocatedFor(size_t num_bytes) override {
    return MaxBytesBulkAllocatedForNonvirtual(num_bytes);
  }
  ALWAYS_INLINE size_t MaxBytesBulkAllocatedForNonvirtual(size_t num_bytes);

  // TODO: NO_THREAD_SAFETY_ANALYSIS because SizeOf() requires that mutator_lock is held.
  template<bool kMaybeIsRunningOnMemoryTool>
  size_t AllocationSizeNonvirtual(mirror::Object* obj, size_t* usable_size)
      NO_THREAD_SAFETY_ANALYSIS;

  allocator::RosAlloc* GetRosAlloc() const {
    return rosalloc_;
  }

  size_t Trim() override;
  void Walk(WalkCallback callback, void* arg) override REQUIRES(!lock_);
  size_t GetFootprint() override;
  size_t GetFootprintLimit() override;
  void SetFootprintLimit(size_t limit) override;

  void Clear() override;

  MallocSpace* CreateInstance(MemMap&& mem_map,
                              const std::string& name,
                              void* allocator,
                              uint8_t* begin,
                              uint8_t* end,
                              uint8_t* limit,
                              size_t growth_limit,
                              bool can_move_objects) override;

  uint64_t GetBytesAllocated() override;
  uint64_t GetObjectsAllocated() override;

  size_t RevokeThreadLocalBuffers(Thread* thread) override;
  size_t RevokeAllThreadLocalBuffers() override;
  void AssertThreadLocalBuffersAreRevoked(Thread* thread);
  void AssertAllThreadLocalBuffersAreRevoked();

  // Returns the class of a recently freed object.
  mirror::Class* FindRecentFreedObject(const mirror::Object* obj);

  bool IsRosAllocSpace() const override {
    return true;
  }

  RosAllocSpace* AsRosAllocSpace() override {
    return this;
  }

  void Verify() REQUIRES(Locks::mutator_lock_) {
    rosalloc_->Verify();
  }

  virtual ~RosAllocSpace();

  bool LogFragmentationAllocFailure(std::ostream& os, size_t failed_alloc_bytes) override {
    return rosalloc_->LogFragmentationAllocFailure(os, failed_alloc_bytes);
  }

  void DumpStats(std::ostream& os);

 protected:
  RosAllocSpace(MemMap&& mem_map,
                size_t initial_size,
                const std::string& name,
                allocator::RosAlloc* rosalloc,
                uint8_t* begin,
                uint8_t* end,
                uint8_t* limit,
                size_t growth_limit,
                bool can_move_objects,
                size_t starting_size,
                bool low_memory_mode);

 private:
  template<bool kThreadSafe = true>
  mirror::Object* AllocCommon(Thread* self, size_t num_bytes, size_t* bytes_allocated,
                              size_t* usable_size, size_t* bytes_tl_bulk_allocated);

  void* CreateAllocator(void* base, size_t morecore_start, size_t initial_size,
                        size_t maximum_size, bool low_memory_mode) override {
    return CreateRosAlloc(
        base, morecore_start, initial_size, maximum_size, low_memory_mode, kRunningOnMemoryTool);
  }
  static allocator::RosAlloc* CreateRosAlloc(void* base, size_t morecore_start, size_t initial_size,
                                             size_t maximum_size, bool low_memory_mode,
                                             bool running_on_memory_tool);

  void InspectAllRosAlloc(void (*callback)(void *start, void *end, size_t num_bytes, void* callback_arg),
                          void* arg, bool do_null_callback_at_end)
      REQUIRES(!Locks::runtime_shutdown_lock_, !Locks::thread_list_lock_);
  void InspectAllRosAllocWithSuspendAll(
      void (*callback)(void *start, void *end, size_t num_bytes, void* callback_arg),
      void* arg, bool do_null_callback_at_end)
      REQUIRES(!Locks::runtime_shutdown_lock_, !Locks::thread_list_lock_);

  // Underlying rosalloc.
  allocator::RosAlloc* rosalloc_;

  const bool low_memory_mode_;

  friend class collector::MarkSweep;

  DISALLOW_COPY_AND_ASSIGN(RosAllocSpace);
};

}  // namespace space
}  // namespace gc
}  // namespace art

#endif  // ART_RUNTIME_GC_SPACE_ROSALLOC_SPACE_H_