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