rocksdb/util/cache_allocator.h
Igor Canadi 1cf5deb8fd Introduce CacheAllocator, a custom allocator for cache blocks (#4437)
Summary:
This is a conceptually simple change, but it touches many files to
pass the allocator through function calls.

We introduce CacheAllocator, which can be used by clients to configure
custom allocator for cache blocks. Our motivation is to hook this up
with folly's `JemallocNodumpAllocator`
(f43ce6d686/folly/experimental/JemallocNodumpAllocator.h),
but there are many other possible use cases.

Additionally, this commit cleans up memory allocation in
`util/compression.h`, making sure that all allocations are wrapped in a
unique_ptr as soon as possible.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4437

Differential Revision: D10132814

Pulled By: yiwu-arbug

fbshipit-source-id: be1343a4b69f6048df127939fea9bbc96969f564
2018-10-02 17:24:58 -07:00

39 lines
1,023 B
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
//
#pragma once
#include "rocksdb/cache_allocator.h"
namespace rocksdb {
struct CustomDeleter {
CustomDeleter(CacheAllocator* a = nullptr) : allocator(a) {}
void operator()(char* ptr) const {
if (allocator) {
allocator->Deallocate(reinterpret_cast<void*>(ptr));
} else {
delete[] ptr;
}
}
CacheAllocator* allocator;
};
using CacheAllocationPtr = std::unique_ptr<char[], CustomDeleter>;
inline CacheAllocationPtr AllocateBlock(size_t size,
CacheAllocator* allocator) {
if (allocator) {
auto block = reinterpret_cast<char*>(allocator->Allocate(size));
return CacheAllocationPtr(block, allocator);
}
return CacheAllocationPtr(new char[size]);
}
} // namespace rocksdb