eigen/unsupported/test/cxx11_eventcount.cpp

138 lines
3.7 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2016 Dmitry Vyukov <dvyukov@google.com>
// Copyright (C) 2016 Benoit Steiner <benoit.steiner.goog@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
#define EIGEN_USE_THREADS
#include "main.h"
#include <Eigen/CXX11/ThreadPool>
#ifdef EIGEN_COMP_MSVC_STRICT
// Visual studio doesn't implementan rand_r() function since its
// implementation of rand()is already thread safe
int rand_r(unsigned int*) {
return rand();
}
#endif
static void test_basic_eventcount()
{
std::vector<EventCount::Waiter> waiters(1);
EventCount ec(waiters);
EventCount::Waiter& w = waiters[0];
ec.Notify(false);
ec.Prewait(&w);
ec.Notify(true);
ec.CommitWait(&w);
ec.Prewait(&w);
ec.CancelWait(&w);
}
// Fake bounded counter-based queue.
struct TestQueue {
std::atomic<int> val_;
static const int kQueueSize = 10;
TestQueue() : val_() {}
~TestQueue() { VERIFY_IS_EQUAL(val_.load(), 0); }
bool Push() {
int val = val_.load(std::memory_order_relaxed);
for (;;) {
VERIFY_GE(val, 0);
VERIFY_LE(val, kQueueSize);
if (val == kQueueSize) return false;
if (val_.compare_exchange_weak(val, val + 1, std::memory_order_relaxed))
return true;
}
}
bool Pop() {
int val = val_.load(std::memory_order_relaxed);
for (;;) {
VERIFY_GE(val, 0);
VERIFY_LE(val, kQueueSize);
if (val == 0) return false;
if (val_.compare_exchange_weak(val, val - 1, std::memory_order_relaxed))
return true;
}
}
bool Empty() { return val_.load(std::memory_order_relaxed) == 0; }
};
const int TestQueue::kQueueSize;
// A number of producers send messages to a set of consumers using a set of
// fake queues. Ensure that it does not crash, consumers don't deadlock and
// number of blocked and unblocked threads match.
static void test_stress_eventcount()
{
const int kThreads = std::thread::hardware_concurrency();
static const int kEvents = 1 << 16;
static const int kQueues = 10;
std::vector<EventCount::Waiter> waiters(kThreads);
EventCount ec(waiters);
TestQueue queues[kQueues];
std::vector<std::unique_ptr<std::thread>> producers;
for (int i = 0; i < kThreads; i++) {
producers.emplace_back(new std::thread([&ec, &queues]() {
unsigned rnd = std::hash<std::thread::id>()(std::this_thread::get_id());
for (int i = 0; i < kEvents; i++) {
unsigned idx = rand_r(&rnd) % kQueues;
if (queues[idx].Push()) {
ec.Notify(false);
continue;
}
std::this_thread::yield();
i--;
}
}));
}
std::vector<std::unique_ptr<std::thread>> consumers;
for (int i = 0; i < kThreads; i++) {
consumers.emplace_back(new std::thread([&ec, &queues, &waiters, i]() {
EventCount::Waiter& w = waiters[i];
unsigned rnd = std::hash<std::thread::id>()(std::this_thread::get_id());
for (int i = 0; i < kEvents; i++) {
unsigned idx = rand_r(&rnd) % kQueues;
if (queues[idx].Pop()) continue;
i--;
ec.Prewait(&w);
bool empty = true;
for (int q = 0; q < kQueues; q++) {
if (!queues[q].Empty()) {
empty = false;
break;
}
}
if (!empty) {
ec.CancelWait(&w);
continue;
}
ec.CommitWait(&w);
}
}));
}
for (int i = 0; i < kThreads; i++) {
producers[i]->join();
consumers[i]->join();
}
}
void test_cxx11_eventcount()
{
CALL_SUBTEST(test_basic_eventcount());
CALL_SUBTEST(test_stress_eventcount());
}