Files
concurrency-in-action/source/listing_5.6.cpp
2018-10-18 00:40:34 -05:00

73 lines
1.7 KiB
C++

#include <atomic>
#include <iostream>
#include <thread>
std::atomic<int> x(0), y(0), z(0);
std::atomic<bool> go(false);
unsigned const loop_count = 10;
struct read_values {
int x, y, z;
};
read_values values1[loop_count];
read_values values2[loop_count];
read_values values3[loop_count];
read_values values4[loop_count];
read_values values5[loop_count];
void
increment(std::atomic<int>* var_to_inc, read_values* values)
{
while (!go) std::this_thread::yield();
for (unsigned i = 0; i < loop_count; ++i) {
values[i].x = x.load(std::memory_order_relaxed);
values[i].y = y.load(std::memory_order_relaxed);
values[i].z = z.load(std::memory_order_relaxed);
var_to_inc->store(i + 1, std::memory_order_relaxed);
std::this_thread::yield();
}
}
void
read_vals(read_values* values)
{
while (!go) std::this_thread::yield();
for (unsigned i = 0; i < loop_count; ++i) {
values[i].x = x.load(std::memory_order_relaxed);
values[i].y = y.load(std::memory_order_relaxed);
values[i].z = z.load(std::memory_order_relaxed);
std::this_thread::yield();
}
}
void
print(read_values* v)
{
for (unsigned i = 0; i < loop_count; ++i) {
if (i)
std::cout << ",";
std::cout << "(" << v[i].x << "," << v[i].y << "," << v[i].z << ")";
}
std::cout << std::endl;
}
int
main()
{
std::thread t1(increment, &x, values1);
std::thread t2(increment, &y, values2);
std::thread t3(increment, &z, values3);
std::thread t4(read_vals, values4);
std::thread t5(read_vals, values5);
go = true;
t5.join();
t4.join();
t3.join();
t2.join();
t1.join();
print(values1);
print(values2);
print(values3);
print(values4);
print(values5);
}