pitrou commented on a change in pull request #9519: URL: https://github.com/apache/arrow/pull/9519#discussion_r578283673
########## File path: cpp/src/arrow/vendored/ProducerConsumerQueue.h ########## @@ -0,0 +1,211 @@ +// Vendored from git tag v2021.02.15.00 + +/* + * Copyright (c) Facebook, Inc. and its affiliates. + * + * 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. + */ + +// @author Bo Hu (b...@fb.com) +// @author Jordan DeLong (delon...@fb.com) + +#pragma once + +#include <atomic> +#include <cassert> +#include <cstdlib> +#include <memory> +#include <stdexcept> +#include <type_traits> +#include <utility> + +namespace folly { + +// Vendored from folly/Portability.h +namespace { +#if defined(__arm__) +#define FOLLY_ARM 1 +#else +#define FOLLY_ARM 0 +#endif + +#if defined(__s390x__) +#define FOLLY_S390X 1 +#else +#define FOLLY_S390X 0 +#endif + +constexpr bool kIsArchArm = FOLLY_ARM == 1; +constexpr bool kIsArchS390X = FOLLY_S390X == 1; +} // namespace + +// Vendored from folly/lang/Align.h +namespace { + +constexpr std::size_t hardware_destructive_interference_size = + (kIsArchArm || kIsArchS390X) ? 64 : 128; Review comment: Ah, I see there's an extensive explanation upstream. Nevermind. https://github.com/facebook/folly/blob/master/folly/lang/Align.h#L108 ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
