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/*
* Copyright 2017 Facebook, Inc.
*
* 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.
*/
#pragma once
/*
* This header defines a few very small mutex types. These are useful
* in highly memory-constrained environments where contention is
* unlikely.
*
* Note: these locks are for use when you aren't likely to contend on
* the critical section, or when the critical section is incredibly
* small. Given that, both of the locks defined in this header are
* inherently unfair: that is, the longer a thread is waiting, the
* longer it waits between attempts to acquire, so newer waiters are
* more likely to get the mutex. For the intended use-case this is
* fine.
*
* @author Keith Adams <kma@fb.com>
* @author Jordan DeLong <delong.j@fb.com>
*/
#include <folly/MicroLock.h>
#include <folly/MicroSpinLock.h>
#include <folly/Portability.h>
#if FOLLY_X64 || FOLLY_A64 || FOLLY_PPC64
#include <folly/PicoSpinLock.h>
#endif