38 lines
1.2 KiB
C++
38 lines
1.2 KiB
C++
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/*
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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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#include <folly/synchronization/ParkingLot.h>
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#include <array>
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namespace folly {
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namespace parking_lot_detail {
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Bucket& Bucket::bucketFor(uint64_t key) {
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constexpr size_t const kNumBuckets = kIsMobile ? 256 : 4096;
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// Statically allocating this lets us use this in allocation-sensitive
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// contexts. This relies on the assumption that std::mutex won't dynamically
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// allocate memory, which we assume to be the case on Linux and iOS.
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static Indestructible<std::array<Bucket, kNumBuckets>> gBuckets;
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return (*gBuckets)[key % kNumBuckets];
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}
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std::atomic<uint64_t> idallocator{0};
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} // namespace parking_lot_detail
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} // namespace folly
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