40 lines
1.1 KiB
C++
40 lines
1.1 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/system/HardwareConcurrency.h>
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#include <thread>
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#include <folly/portability/Sched.h>
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namespace folly {
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unsigned int hardware_concurrency() noexcept {
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#if defined(__linux__) && !defined(__ANDROID__)
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cpu_set_t cpuset;
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if (!sched_getaffinity(0, sizeof(cpuset), &cpuset)) {
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auto count = CPU_COUNT(&cpuset);
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if (count != 0) {
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return count;
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}
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}
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#endif
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return std::thread::hardware_concurrency();
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}
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} // namespace folly
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