vn-verdnaturachat/ios/Pods/Flipper-Folly/folly/synchronization/ParkingLot.cpp

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