1 // Copyright 2018 The Abseil Authors. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 // See also //absl/synchronization:mutex_benchmark for a comparison of SpinLock 16 // and Mutex performance under varying levels of contention. 17 18 #include "absl/base/internal/raw_logging.h" 19 #include "absl/base/internal/scheduling_mode.h" 20 #include "absl/base/internal/spinlock.h" 21 #include "absl/synchronization/internal/create_thread_identity.h" 22 #include "benchmark/benchmark.h" 23 24 namespace { 25 26 template <absl::base_internal::SchedulingMode scheduling_mode> BM_SpinLock(benchmark::State & state)27static void BM_SpinLock(benchmark::State& state) { 28 // Ensure a ThreadIdentity is installed. 29 ABSL_INTERNAL_CHECK( 30 absl::synchronization_internal::GetOrCreateCurrentThreadIdentity() != 31 nullptr, 32 "GetOrCreateCurrentThreadIdentity() failed"); 33 34 static auto* spinlock = new absl::base_internal::SpinLock(scheduling_mode); 35 for (auto _ : state) { 36 absl::base_internal::SpinLockHolder holder(spinlock); 37 } 38 } 39 40 BENCHMARK_TEMPLATE(BM_SpinLock, 41 absl::base_internal::SCHEDULE_KERNEL_ONLY) 42 ->UseRealTime() 43 ->Threads(1) 44 ->ThreadPerCpu(); 45 46 BENCHMARK_TEMPLATE(BM_SpinLock, 47 absl::base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL) 48 ->UseRealTime() 49 ->Threads(1) 50 ->ThreadPerCpu(); 51 52 } // namespace 53