2 * Copyright 2016 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #include <folly/Baton.h>
19 #include <semaphore.h>
22 #include <gtest/gtest.h>
24 #include <folly/Benchmark.h>
25 #include <folly/portability/GFlags.h>
26 #include <folly/test/BatonTestHelpers.h>
27 #include <folly/test/DeterministicSchedule.h>
29 using namespace folly;
30 using namespace folly::test;
31 using folly::detail::EmulatedFutexAtomic;
33 typedef DeterministicSchedule DSched;
35 BENCHMARK(baton_pingpong, iters) { run_pingpong_test<std::atomic>(iters); }
37 BENCHMARK(baton_pingpong_emulated_futex, iters) {
38 run_pingpong_test<EmulatedFutexAtomic>(iters);
41 BENCHMARK(posix_sem_pingpong, iters) {
44 sem_t* b = sems + 2; // to get it on a different cache line
48 auto thr = std::thread([=] {
49 for (size_t i = 0; i < iters; ++i) {
54 for (size_t i = 0; i < iters; ++i) {
61 // I am omitting a benchmark result snapshot because these microbenchmarks
62 // mainly illustrate that PreBlockAttempts is very effective for rapid
63 // handoffs. The performance of Baton and sem_t is essentially identical
64 // to the required futex calls for the blocking case
66 int main(int argc, char** argv) {
67 testing::InitGoogleTest(&argc, argv);
68 gflags::ParseCommandLineFlags(&argc, &argv, true);
70 auto rv = RUN_ALL_TESTS();
71 if (!rv && FLAGS_benchmark) {
72 folly::runBenchmarks();