chromium/third_party/dawn/src/dawn/native/BuddyMemoryAllocator.h

// Copyright 2019 The Dawn & Tint Authors
//
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// modification, are permitted provided that the following conditions are met:
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//    list of conditions and the following disclaimer.
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#ifndef SRC_DAWN_NATIVE_BUDDYMEMORYALLOCATOR_H_
#define SRC_DAWN_NATIVE_BUDDYMEMORYALLOCATOR_H_

#include <memory>
#include <vector>

#include "dawn/native/BuddyAllocator.h"
#include "dawn/native/Error.h"
#include "dawn/native/ResourceMemoryAllocation.h"
#include "partition_alloc/pointers/raw_ptr.h"

namespace dawn::native {

class ResourceHeapAllocator;

// BuddyMemoryAllocator uses the buddy allocator to sub-allocate blocks of device
// memory created by MemoryAllocator clients. It creates a very large buddy system
// where backing device memory blocks equal a specified level in the system.
//
// Upon sub-allocating, the offset gets mapped to device memory by computing the corresponding
// memory index and should the memory not exist, it is created. If two sub-allocations share the
// same memory index, the memory refcount is incremented to ensure de-allocating one doesn't
// release the other prematurely.
//
// The MemoryAllocator should return ResourceHeaps that are all compatible with each other.
// It should also outlive all the resources that are in the buddy allocator.
class BuddyMemoryAllocator { … };

}  // namespace dawn::native

#endif  // SRC_DAWN_NATIVE_BUDDYMEMORYALLOCATOR_H_