// Copyright 2018 The Abseil Authors.
//
// 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
//
// https://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.
// See also //absl/synchronization:mutex_benchmark for a comparison of SpinLock
// and Mutex performance under varying levels of contention.
#include "absl/base/internal/raw_logging.h"
#include "absl/base/internal/scheduling_mode.h"
#include "absl/base/internal/spinlock.h"
#include "absl/base/no_destructor.h"
#include "absl/synchronization/internal/create_thread_identity.h"
#include "benchmark/benchmark.h"
namespace {
template <absl::base_internal::SchedulingMode scheduling_mode>
static void BM_TryLock(benchmark::State& state) {
// Ensure a ThreadIdentity is installed so that KERNEL_ONLY has an effect.
ABSL_INTERNAL_CHECK(
absl::synchronization_internal::GetOrCreateCurrentThreadIdentity() !=
nullptr,
"GetOrCreateCurrentThreadIdentity() failed");
static absl::NoDestructor<absl::base_internal::SpinLock> spinlock(
scheduling_mode);
for (auto _ : state) {
if (spinlock->TryLock()) spinlock->Unlock();
}
}
template <absl::base_internal::SchedulingMode scheduling_mode>
static void BM_SpinLock(benchmark::State& state) {
// Ensure a ThreadIdentity is installed so that KERNEL_ONLY has an effect.
ABSL_INTERNAL_CHECK(
absl::synchronization_internal::GetOrCreateCurrentThreadIdentity() !=
nullptr,
"GetOrCreateCurrentThreadIdentity() failed");
static absl::NoDestructor<absl::base_internal::SpinLock> spinlock(
scheduling_mode);
for (auto _ : state) {
absl::base_internal::SpinLockHolder holder(spinlock.get());
}
}
BENCHMARK_TEMPLATE(BM_SpinLock,
absl::base_internal::SCHEDULE_KERNEL_ONLY)
->UseRealTime()
->Threads(1)
->ThreadPerCpu();
BENCHMARK_TEMPLATE(BM_SpinLock,
absl::base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL)
->UseRealTime()
->Threads(1)
->ThreadPerCpu();
BENCHMARK_TEMPLATE(BM_TryLock, absl::base_internal::SCHEDULE_KERNEL_ONLY)
->UseRealTime()
->Threads(1)
->ThreadPerCpu();
BENCHMARK_TEMPLATE(BM_TryLock,
absl::base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL)
->UseRealTime()
->Threads(1)
->ThreadPerCpu();
} // namespace