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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef TEST_BENCHMARK_ATOMIC_WAIT_HELPER_H
#define TEST_BENCHMARK_ATOMIC_WAIT_HELPER_H
#include <atomic>
#include <chrono>
#include <exception>
#include <stop_token>
#include <thread>
struct HighPrioTask {
sched_param param;
pthread_attr_t attr_t;
pthread_t thread;
std::atomic_bool stopped{false};
HighPrioTask(const HighPrioTask&) = delete;
HighPrioTask() {
pthread_attr_init(&attr_t);
pthread_attr_setschedpolicy(&attr_t, SCHED_FIFO);
param.sched_priority = sched_get_priority_max(SCHED_FIFO);
pthread_attr_setschedparam(&attr_t, ¶m);
pthread_attr_setinheritsched(&attr_t, PTHREAD_EXPLICIT_SCHED);
auto thread_fun = [](void* arg) -> void* {
auto* stop = reinterpret_cast<std::atomic_bool*>(arg);
while (!stop->load(std::memory_order_relaxed)) {
// spin
}
return nullptr;
};
if (pthread_create(&thread, &attr_t, thread_fun, &stopped) != 0) {
throw std::runtime_error("failed to create thread");
}
}
~HighPrioTask() {
stopped = true;
pthread_attr_destroy(&attr_t);
pthread_join(thread, nullptr);
}
};
template <std::size_t N>
struct NumHighPrioTasks {
static constexpr auto value = N;
};
template <std::size_t N>
struct NumWaitingThreads {
static constexpr auto value = N;
};
template <std::size_t N>
struct NumberOfAtomics {
static constexpr auto value = N;
};
struct KeepNotifying {
template <class Atomic>
static void notify(Atomic& a, std::stop_token st) {
while (!st.stop_requested()) {
a.fetch_add(1, std::memory_order_relaxed);
a.notify_all();
}
}
};
template <std::size_t N>
struct NotifyEveryNus {
template <class Atomic>
static void notify(Atomic& a, std::stop_token st) {
while (!st.stop_requested()) {
auto start = std::chrono::system_clock::now();
a.fetch_add(1, std::memory_order_relaxed);
a.notify_all();
while (std::chrono::system_clock::now() - start < std::chrono::microseconds{N}) {
}
}
}
};
#endif // TEST_BENCHMARK_ATOMIC_WAIT_HELPER_H
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