172 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// This benchmark is very expensive and we don't want to run it on a regular basis,12// only to ensure the code doesn't rot.13// REQUIRES: enable-benchmarks=dry-run14 15#include "atomic_wait_helper.h"16 17#include <atomic>18#include <cstdint>19#include <numeric>20#include <stop_token>21#include <thread>22#include <chrono>23#include <array>24 25#include "benchmark/benchmark.h"26#include "make_test_thread.h"27 28using namespace std::chrono_literals;29 30template <class NotifyPolicy, class NumWaitingThreads, class NumPrioTasks>31void BM_1_atomic_multi_waiter_1_notifier(benchmark::State& state) {32 [[maybe_unused]] std::array<HighPrioTask, NumPrioTasks::value> tasks{};33 34 std::atomic<std::uint64_t> a;35 auto notify_func = [&](std::stop_token st) { NotifyPolicy::notify(a, st); };36 37 std::uint64_t total_loop_test_param = state.range(0);38 constexpr auto num_waiting_threads = NumWaitingThreads::value;39 std::vector<std::jthread> wait_threads;40 wait_threads.reserve(num_waiting_threads);41 42 auto notify_thread = support::make_test_jthread(notify_func);43 44 std::atomic<std::uint64_t> start_flag = 0;45 std::atomic<std::uint64_t> done_count = 0;46 auto wait_func = [&a, &start_flag, &done_count, total_loop_test_param](std::stop_token st) {47 auto old_start = 0;48 while (!st.stop_requested()) {49 start_flag.wait(old_start);50 old_start = start_flag.load();51 for (std::uint64_t i = 0; i < total_loop_test_param; ++i) {52 auto old = a.load(std::memory_order_relaxed);53 a.wait(old);54 }55 done_count.fetch_add(1);56 }57 };58 59 for (size_t i = 0; i < num_waiting_threads; ++i) {60 wait_threads.emplace_back(support::make_test_jthread(wait_func));61 }62 63 for (auto _ : state) {64 done_count = 0;65 start_flag.fetch_add(1);66 start_flag.notify_all();67 while (done_count < num_waiting_threads) {68 std::this_thread::yield();69 }70 }71 for (auto& t : wait_threads) {72 t.request_stop();73 }74 start_flag.fetch_add(1);75 start_flag.notify_all();76 for (auto& t : wait_threads) {77 t.join();78 }79}80 81BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<3>, NumHighPrioTasks<0>>)82 ->RangeMultiplier(2)83 ->Range(1 << 14, 1 << 16);84BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<7>, NumHighPrioTasks<0>>)85 ->RangeMultiplier(2)86 ->Range(1 << 12, 1 << 14);87BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<15>, NumHighPrioTasks<0>>)88 ->RangeMultiplier(2)89 ->Range(1 << 10, 1 << 12);90 91BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<3>, NumHighPrioTasks<0>>)92 ->RangeMultiplier(2)93 ->Range(1 << 10, 1 << 12);94BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<7>, NumHighPrioTasks<0>>)95 ->RangeMultiplier(2)96 ->Range(1 << 8, 1 << 10);97BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<15>, NumHighPrioTasks<0>>)98 ->RangeMultiplier(2)99 ->Range(1 << 6, 1 << 8);100 101BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<3>, NumHighPrioTasks<0>>)102 ->RangeMultiplier(2)103 ->Range(1 << 8, 1 << 10);104BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<7>, NumHighPrioTasks<0>>)105 ->RangeMultiplier(2)106 ->Range(1 << 6, 1 << 8);107BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<15>, NumHighPrioTasks<0>>)108 ->RangeMultiplier(2)109 ->Range(1 << 4, 1 << 6);110 111BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<3>, NumHighPrioTasks<4>>)112 ->RangeMultiplier(2)113 ->Range(1 << 8, 1 << 10);114BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<7>, NumHighPrioTasks<4>>)115 ->RangeMultiplier(2)116 ->Range(1 << 6, 1 << 8);117BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<15>, NumHighPrioTasks<4>>)118 ->RangeMultiplier(2)119 ->Range(1 << 4, 1 << 6);120 121BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<3>, NumHighPrioTasks<4>>)122 ->RangeMultiplier(2)123 ->Range(1 << 8, 1 << 10);124BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<7>, NumHighPrioTasks<4>>)125 ->RangeMultiplier(2)126 ->Range(1 << 6, 1 << 8);127BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<15>, NumHighPrioTasks<4>>)128 ->RangeMultiplier(2)129 ->Range(1 << 4, 1 << 6);130 131BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<3>, NumHighPrioTasks<4>>)132 ->RangeMultiplier(2)133 ->Range(1 << 8, 1 << 10);134BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<7>, NumHighPrioTasks<4>>)135 ->RangeMultiplier(2)136 ->Range(1 << 6, 1 << 8);137BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<15>, NumHighPrioTasks<4>>)138 ->RangeMultiplier(2)139 ->Range(1 << 4, 1 << 6);140 141BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<3>, NumHighPrioTasks<7>>)142 ->RangeMultiplier(2)143 ->Range(1 << 4, 1 << 6);144BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<7>, NumHighPrioTasks<7>>)145 ->RangeMultiplier(2)146 ->Range(1 << 3, 1 << 5);147BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<15>, NumHighPrioTasks<7>>)148 ->RangeMultiplier(2)149 ->Range(1 << 2, 1 << 4);150 151BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<3>, NumHighPrioTasks<7>>)152 ->RangeMultiplier(2)153 ->Range(1 << 3, 1 << 5);154BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<7>, NumHighPrioTasks<7>>)155 ->RangeMultiplier(2)156 ->Range(1 << 2, 1 << 4);157BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<15>, NumHighPrioTasks<7>>)158 ->RangeMultiplier(2)159 ->Range(1 << 1, 1 << 3);160 161BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<3>, NumHighPrioTasks<7>>)162 ->RangeMultiplier(2)163 ->Range(1 << 3, 1 << 5);164BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<7>, NumHighPrioTasks<7>>)165 ->RangeMultiplier(2)166 ->Range(1 << 2, 1 << 4);167BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<15>, NumHighPrioTasks<7>>)168 ->RangeMultiplier(2)169 ->Range(1 << 1, 1 << 3);170 171BENCHMARK_MAIN();172