A Walkthrough Using Acquire and Release Fences

We’ll take the example from my previous post and modify it to use C++11’s standalone acquire and release fences. Here’s the SendTestMessage function. The atomic write is now relaxed, and a release fence has been placed immediately before it.

void SendTestMessage(void* param)
{
   
    // Copy to shared memory using non-atomic stores.
    g_payload.tick  = clock();
    g_payload.str   = "TestMessage";
    g_payload.param = param;
    
    // Release fence.
    std::atomic_thread_fence(std::memory_order_release);

    // Perform an atomic write to indicate that the message is ready.
    g_guard.store(1, std