Mutex

Mutex Asssignment

• A shared resource is a resource that can be used by more than one task. Each task should gain exclusive access to the shared resource to prevent data corruption. This is called mutual exclusion.
• Shared I/O devices require the use of mutual exclusion; for example, a task might need exclusive access to a printer.
• We will consider printf (uses UART) function as a shared resource because any task may call at any time to print some thing.

• Create two tasks, Task1 and Task2 with equal priorities as continuous processing tasks.

  Task1 displays as “Task1 is running …” and Task2 as “Task2 is running …”

  Observe the output. Do you see any data corruption in the output?

• Now, use mutual exclusion for printf function in both the Tasks.

  Observe the output

Note: Use atomMutexCreate(), atomMutexGet() and atomMutexPut() functions.

References

1. Introduction to atomthreads
2. atomthreads kernel Reference
3. atomthreads Documentation