diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 18:24:20 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 18:24:20 +0000 |
commit | 483eb2f56657e8e7f419ab1a4fab8dce9ade8609 (patch) | |
tree | e5d88d25d870d5dedacb6bbdbe2a966086a0a5cf /src/msg/async/dpdk/circular_buffer.h | |
parent | Initial commit. (diff) | |
download | ceph-483eb2f56657e8e7f419ab1a4fab8dce9ade8609.tar.xz ceph-483eb2f56657e8e7f419ab1a4fab8dce9ade8609.zip |
Adding upstream version 14.2.21.upstream/14.2.21upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/msg/async/dpdk/circular_buffer.h')
-rw-r--r-- | src/msg/async/dpdk/circular_buffer.h | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/src/msg/async/dpdk/circular_buffer.h b/src/msg/async/dpdk/circular_buffer.h new file mode 100644 index 00000000..2c92c120 --- /dev/null +++ b/src/msg/async/dpdk/circular_buffer.h @@ -0,0 +1,347 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +/* + * This file is open source software, licensed to you under the terms + * of the Apache License, Version 2.0 (the "License"). See the NOTICE file + * distributed with this work for additional information regarding copyright + * ownership. 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. + */ +/* + * Copyright (C) 2014 Cloudius Systems, Ltd. + */ + +#ifndef CEPH_CIRCULAR_BUFFER_HH_ +#define CEPH_CIRCULAR_BUFFER_HH_ + +// A growable double-ended queue container that can be efficiently +// extended (and shrunk) from both ends. Implementation is a single +// storage vector. +// +// Similar to libstdc++'s std::deque, except that it uses a single level +// store, and so is more efficient for simple stored items. +// Similar to boost::circular_buffer_space_optimized, except it uses +// uninitialized storage for unoccupied elements (and thus move/copy +// constructors instead of move/copy assignments, which are less efficient). + +#include <memory> +#include <algorithm> + +#include "transfer.h" + +template <typename T, typename Alloc = std::allocator<T>> +class circular_buffer { + struct impl : Alloc { + T* storage = nullptr; + // begin, end interpreted (mod capacity) + size_t begin = 0; + size_t end = 0; + size_t capacity = 0; + }; + impl _impl; + public: + using value_type = T; + using size_type = size_t; + using reference = T&; + using pointer = T*; + using const_reference = const T&; + using const_pointer = const T*; + public: + circular_buffer() = default; + circular_buffer(circular_buffer&& X); + circular_buffer(const circular_buffer& X) = delete; + ~circular_buffer(); + circular_buffer& operator=(const circular_buffer&) = delete; + circular_buffer& operator=(circular_buffer&&) = delete; + void push_front(const T& data); + void push_front(T&& data); + template <typename... A> + void emplace_front(A&&... args); + void push_back(const T& data); + void push_back(T&& data); + template <typename... A> + void emplace_back(A&&... args); + T& front(); + T& back(); + void pop_front(); + void pop_back(); + bool empty() const; + size_t size() const; + size_t capacity() const; + T& operator[](size_t idx); + template <typename Func> + void for_each(Func func); + // access an element, may return wrong or destroyed element + // only useful if you do not rely on data accuracy (e.g. prefetch) + T& access_element_unsafe(size_t idx); + private: + void expand(); + void maybe_expand(size_t nr = 1); + size_t mask(size_t idx) const; + + template<typename CB, typename ValueType> + struct cbiterator : std::iterator<std::random_access_iterator_tag, ValueType> { + typedef std::iterator<std::random_access_iterator_tag, ValueType> super_t; + + ValueType& operator*() const { return cb->_impl.storage[cb->mask(idx)]; } + ValueType* operator->() const { return &cb->_impl.storage[cb->mask(idx)]; } + // prefix + cbiterator<CB, ValueType>& operator++() { + idx++; + return *this; + } + // postfix + cbiterator<CB, ValueType> operator++(int unused) { + auto v = *this; + idx++; + return v; + } + // prefix + cbiterator<CB, ValueType>& operator--() { + idx--; + return *this; + } + // postfix + cbiterator<CB, ValueType> operator--(int unused) { + auto v = *this; + idx--; + return v; + } + cbiterator<CB, ValueType> operator+(typename super_t::difference_type n) const { + return cbiterator<CB, ValueType>(cb, idx + n); + } + cbiterator<CB, ValueType> operator-(typename super_t::difference_type n) const { + return cbiterator<CB, ValueType>(cb, idx - n); + } + cbiterator<CB, ValueType>& operator+=(typename super_t::difference_type n) { + idx += n; + return *this; + } + cbiterator<CB, ValueType>& operator-=(typename super_t::difference_type n) { + idx -= n; + return *this; + } + bool operator==(const cbiterator<CB, ValueType>& rhs) const { + return idx == rhs.idx; + } + bool operator!=(const cbiterator<CB, ValueType>& rhs) const { + return idx != rhs.idx; + } + bool operator<(const cbiterator<CB, ValueType>& rhs) const { + return idx < rhs.idx; + } + bool operator>(const cbiterator<CB, ValueType>& rhs) const { + return idx > rhs.idx; + } + bool operator>=(const cbiterator<CB, ValueType>& rhs) const { + return idx >= rhs.idx; + } + bool operator<=(const cbiterator<CB, ValueType>& rhs) const { + return idx <= rhs.idx; + } + typename super_t::difference_type operator-(const cbiterator<CB, ValueType>& rhs) const { + return idx - rhs.idx; + } + private: + CB* cb; + size_t idx; + cbiterator<CB, ValueType>(CB* b, size_t i) : cb(b), idx(i) {} + friend class circular_buffer; + }; + friend class iterator; + + public: + typedef cbiterator<circular_buffer, T> iterator; + typedef cbiterator<const circular_buffer, const T> const_iterator; + + iterator begin() { + return iterator(this, _impl.begin); + } + const_iterator begin() const { + return const_iterator(this, _impl.begin); + } + iterator end() { + return iterator(this, _impl.end); + } + const_iterator end() const { + return const_iterator(this, _impl.end); + } + const_iterator cbegin() const { + return const_iterator(this, _impl.begin); + } + const_iterator cend() const { + return const_iterator(this, _impl.end); + } +}; + +template <typename T, typename Alloc> +inline size_t circular_buffer<T, Alloc>::mask(size_t idx) const { + return idx & (_impl.capacity - 1); +} + +template <typename T, typename Alloc> +inline bool circular_buffer<T, Alloc>::empty() const { + return _impl.begin == _impl.end; +} + +template <typename T, typename Alloc> +inline size_t circular_buffer<T, Alloc>::size() const { + return _impl.end - _impl.begin; +} + +template <typename T, typename Alloc> +inline size_t circular_buffer<T, Alloc>::capacity() const { + return _impl.capacity; +} + +template <typename T, typename Alloc> +inline circular_buffer<T, Alloc>::circular_buffer(circular_buffer&& x) + : _impl(std::move(x._impl)) { + x._impl = {}; +} + +template <typename T, typename Alloc> +template <typename Func> +inline void circular_buffer<T, Alloc>::for_each(Func func) { + auto s = _impl.storage; + auto m = _impl.capacity - 1; + for (auto i = _impl.begin; i != _impl.end; ++i) { + func(s[i & m]); + } +} + +template <typename T, typename Alloc> +inline circular_buffer<T, Alloc>::~circular_buffer() { + for_each([this] (T& obj) { + _impl.destroy(&obj); + }); + _impl.deallocate(_impl.storage, _impl.capacity); +} + +template <typename T, typename Alloc> +void circular_buffer<T, Alloc>::expand() { + auto new_cap = std::max<size_t>(_impl.capacity * 2, 1); + auto new_storage = _impl.allocate(new_cap); + auto p = new_storage; + try { + for_each([this, &p] (T& obj) { + transfer_pass1(_impl, &obj, p); + p++; + }); + } catch (...) { + while (p != new_storage) { + _impl.destroy(--p); + } + _impl.deallocate(new_storage, new_cap); + throw; + } + p = new_storage; + for_each([this, &p] (T& obj) { + transfer_pass2(_impl, &obj, p++); + }); + std::swap(_impl.storage, new_storage); + std::swap(_impl.capacity, new_cap); + _impl.begin = 0; + _impl.end = p - _impl.storage; + _impl.deallocate(new_storage, new_cap); +} + +template <typename T, typename Alloc> +inline void circular_buffer<T, Alloc>::maybe_expand(size_t nr) { + if (_impl.end - _impl.begin + nr > _impl.capacity) { + expand(); + } +} + +template <typename T, typename Alloc> +inline void circular_buffer<T, Alloc>::push_front(const T& data) { + maybe_expand(); + auto p = &_impl.storage[mask(_impl.begin - 1)]; + _impl.construct(p, data); + --_impl.begin; +} + +template <typename T, typename Alloc> +inline void circular_buffer<T, Alloc>::push_front(T&& data) { + maybe_expand(); + auto p = &_impl.storage[mask(_impl.begin - 1)]; + _impl.construct(p, std::move(data)); + --_impl.begin; +} + +template <typename T, typename Alloc> +template <typename... Args> +inline void circular_buffer<T, Alloc>::emplace_front(Args&&... args) { + maybe_expand(); + auto p = &_impl.storage[mask(_impl.begin - 1)]; + _impl.construct(p, std::forward<Args>(args)...); + --_impl.begin; +} + +template <typename T, typename Alloc> +inline void circular_buffer<T, Alloc>::push_back(const T& data) { + maybe_expand(); + auto p = &_impl.storage[mask(_impl.end)]; + _impl.construct(p, data); + ++_impl.end; +} + +template <typename T, typename Alloc> +inline void circular_buffer<T, Alloc>::push_back(T&& data) { + maybe_expand(); + auto p = &_impl.storage[mask(_impl.end)]; + _impl.construct(p, std::move(data)); + ++_impl.end; +} + +template <typename T, typename Alloc> +template <typename... Args> +inline void circular_buffer<T, Alloc>::emplace_back(Args&&... args) { + maybe_expand(); + auto p = &_impl.storage[mask(_impl.end)]; + _impl.construct(p, std::forward<Args>(args)...); + ++_impl.end; +} + +template <typename T, typename Alloc> +inline T& circular_buffer<T, Alloc>::front() { + return _impl.storage[mask(_impl.begin)]; +} + +template <typename T, typename Alloc> +inline T& circular_buffer<T, Alloc>::back() { + return _impl.storage[mask(_impl.end - 1)]; +} + +template <typename T, typename Alloc> +inline void circular_buffer<T, Alloc>::pop_front() { + _impl.destroy(&front()); + ++_impl.begin; +} + +template <typename T, typename Alloc> +inline void circular_buffer<T, Alloc>::pop_back() { + _impl.destroy(&back()); + --_impl.end; +} + +template <typename T, typename Alloc> +inline T& circular_buffer<T, Alloc>::operator[](size_t idx) { + return _impl.storage[mask(_impl.begin + idx)]; +} + +template <typename T, typename Alloc> +inline T& circular_buffer<T, Alloc>::access_element_unsafe(size_t idx) { + return _impl.storage[mask(_impl.begin + idx)]; +} + +#endif /* CEPH_CIRCULAR_BUFFER_HH_ */ |