43 lines
1.5 KiB
C
43 lines
1.5 KiB
C
/*
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#pragma once
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/*
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* This header defines a few very small mutex types. These are useful
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* in highly memory-constrained environments where contention is
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* unlikely.
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*
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* Note: these locks are for use when you aren't likely to contend on
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* the critical section, or when the critical section is incredibly
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* small. Given that, both of the locks defined in this header are
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* inherently unfair: that is, the longer a thread is waiting, the
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* longer it waits between attempts to acquire, so newer waiters are
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* more likely to get the mutex. For the intended use-case this is
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* fine.
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*
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* @author Keith Adams <kma@fb.com>
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* @author Jordan DeLong <delong.j@fb.com>
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*/
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#include <folly/MicroLock.h>
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#include <folly/synchronization/MicroSpinLock.h>
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#include <folly/Portability.h>
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#if FOLLY_X64 || FOLLY_AARCH64 || FOLLY_PPC64
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#include <folly/synchronization/PicoSpinLock.h>
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#endif
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