xref: /llvm-project/libcxx/test/benchmarks/atomic_wait_multi_waiter_1_notifier.bench.cpp (revision 699f19605579f25083152a9ad21e14c2751d5d66)
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-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: c++03, c++11, c++14, c++17
10 
11 #include "atomic_wait_helper.h"
12 
13 #include <atomic>
14 #include <cstdint>
15 #include <numeric>
16 #include <stop_token>
17 #include <thread>
18 #include <chrono>
19 #include <array>
20 
21 #include "benchmark/benchmark.h"
22 #include "make_test_thread.h"
23 
24 using namespace std::chrono_literals;
25 
26 template <class NotifyPolicy, class NumWaitingThreads, class NumPrioTasks>
27 void BM_1_atomic_multi_waiter_1_notifier(benchmark::State& state) {
28   [[maybe_unused]] std::array<HighPrioTask, NumPrioTasks::value> tasks{};
29 
30   std::atomic<std::uint64_t> a;
31   auto notify_func = [&](std::stop_token st) { NotifyPolicy::notify(a, st); };
32 
33   std::uint64_t total_loop_test_param = state.range(0);
34   constexpr auto num_waiting_threads  = NumWaitingThreads::value;
35   std::vector<std::jthread> wait_threads;
36   wait_threads.reserve(num_waiting_threads);
37 
38   auto notify_thread = support::make_test_jthread(notify_func);
39 
40   std::atomic<std::uint64_t> start_flag = 0;
41   std::atomic<std::uint64_t> done_count = 0;
42   auto wait_func                        = [&a, &start_flag, &done_count, total_loop_test_param](std::stop_token st) {
43     auto old_start = 0;
44     while (!st.stop_requested()) {
45       start_flag.wait(old_start);
46       old_start = start_flag.load();
47       for (std::uint64_t i = 0; i < total_loop_test_param; ++i) {
48         auto old = a.load(std::memory_order_relaxed);
49         a.wait(old);
50       }
51       done_count.fetch_add(1);
52     }
53   };
54 
55   for (size_t i = 0; i < num_waiting_threads; ++i) {
56     wait_threads.emplace_back(support::make_test_jthread(wait_func));
57   }
58 
59   for (auto _ : state) {
60     done_count = 0;
61     start_flag.fetch_add(1);
62     start_flag.notify_all();
63     while (done_count < num_waiting_threads) {
64       std::this_thread::yield();
65     }
66   }
67   for (auto& t : wait_threads) {
68     t.request_stop();
69   }
70   start_flag.fetch_add(1);
71   start_flag.notify_all();
72   for (auto& t : wait_threads) {
73     t.join();
74   }
75 }
76 
77 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<3>, NumHighPrioTasks<0>>)
78     ->RangeMultiplier(2)
79     ->Range(1 << 14, 1 << 16);
80 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<7>, NumHighPrioTasks<0>>)
81     ->RangeMultiplier(2)
82     ->Range(1 << 12, 1 << 14);
83 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<15>, NumHighPrioTasks<0>>)
84     ->RangeMultiplier(2)
85     ->Range(1 << 10, 1 << 12);
86 
87 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<3>, NumHighPrioTasks<0>>)
88     ->RangeMultiplier(2)
89     ->Range(1 << 10, 1 << 12);
90 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<7>, NumHighPrioTasks<0>>)
91     ->RangeMultiplier(2)
92     ->Range(1 << 8, 1 << 10);
93 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<15>, NumHighPrioTasks<0>>)
94     ->RangeMultiplier(2)
95     ->Range(1 << 6, 1 << 8);
96 
97 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<3>, NumHighPrioTasks<0>>)
98     ->RangeMultiplier(2)
99     ->Range(1 << 8, 1 << 10);
100 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<7>, NumHighPrioTasks<0>>)
101     ->RangeMultiplier(2)
102     ->Range(1 << 6, 1 << 8);
103 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<15>, NumHighPrioTasks<0>>)
104     ->RangeMultiplier(2)
105     ->Range(1 << 4, 1 << 6);
106 
107 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<3>, NumHighPrioTasks<4>>)
108     ->RangeMultiplier(2)
109     ->Range(1 << 8, 1 << 10);
110 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<7>, NumHighPrioTasks<4>>)
111     ->RangeMultiplier(2)
112     ->Range(1 << 6, 1 << 8);
113 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<15>, NumHighPrioTasks<4>>)
114     ->RangeMultiplier(2)
115     ->Range(1 << 4, 1 << 6);
116 
117 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<3>, NumHighPrioTasks<4>>)
118     ->RangeMultiplier(2)
119     ->Range(1 << 8, 1 << 10);
120 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<7>, NumHighPrioTasks<4>>)
121     ->RangeMultiplier(2)
122     ->Range(1 << 6, 1 << 8);
123 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<15>, NumHighPrioTasks<4>>)
124     ->RangeMultiplier(2)
125     ->Range(1 << 4, 1 << 6);
126 
127 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<3>, NumHighPrioTasks<4>>)
128     ->RangeMultiplier(2)
129     ->Range(1 << 8, 1 << 10);
130 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<7>, NumHighPrioTasks<4>>)
131     ->RangeMultiplier(2)
132     ->Range(1 << 6, 1 << 8);
133 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<15>, NumHighPrioTasks<4>>)
134     ->RangeMultiplier(2)
135     ->Range(1 << 4, 1 << 6);
136 
137 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<3>, NumHighPrioTasks<7>>)
138     ->RangeMultiplier(2)
139     ->Range(1 << 4, 1 << 6);
140 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<7>, NumHighPrioTasks<7>>)
141     ->RangeMultiplier(2)
142     ->Range(1 << 3, 1 << 5);
143 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<KeepNotifying, NumWaitingThreads<15>, NumHighPrioTasks<7>>)
144     ->RangeMultiplier(2)
145     ->Range(1 << 2, 1 << 4);
146 
147 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<3>, NumHighPrioTasks<7>>)
148     ->RangeMultiplier(2)
149     ->Range(1 << 3, 1 << 5);
150 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<7>, NumHighPrioTasks<7>>)
151     ->RangeMultiplier(2)
152     ->Range(1 << 2, 1 << 4);
153 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<50>, NumWaitingThreads<15>, NumHighPrioTasks<7>>)
154     ->RangeMultiplier(2)
155     ->Range(1 << 1, 1 << 3);
156 
157 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<3>, NumHighPrioTasks<7>>)
158     ->RangeMultiplier(2)
159     ->Range(1 << 3, 1 << 5);
160 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<7>, NumHighPrioTasks<7>>)
161     ->RangeMultiplier(2)
162     ->Range(1 << 2, 1 << 4);
163 BENCHMARK(BM_1_atomic_multi_waiter_1_notifier<NotifyEveryNus<100>, NumWaitingThreads<15>, NumHighPrioTasks<7>>)
164     ->RangeMultiplier(2)
165     ->Range(1 << 1, 1 << 3);
166 
167 BENCHMARK_MAIN();
168