std::barrier

Introduction

An std::barrier is similar to a std::latch.

There are two differences between a std::latch and a std::barrier. First, you can use a std::barrier more than once, and second, you can set the counter for the next step (iteration). Immediately after the counter becomes zero, the so-called completion step starts. In this completion step, a callable is invoked. The std::barrier gets its callable in its constructor.

The completion step performs the following steps:

1. All threads are blocked.
2. An arbitrary thread is unblocked and executes the callable.
3. If the completion step is done, all threads are unblocked.

Example and analysis

Now, let us have a closer look at the interface of a std::barrier.