Operating Systems · Concurrency

Locks and mutual exclusion

A lock that lets only one thread at a time execute a critical section.

Also known as: mutex, spinlocks, critical section protection.

Start a lesson on Locks and mutual exclusion

Learn first

• Race conditions and critical sections: What goes wrong when two threads touch the same data at the same time without coordination.

Leads to

• Semaphores and condition variables: Counting locks and wait-until-signaled primitives, more flexible tools than a plain mutex.
• Deadlock: A cycle of threads each waiting on a lock another one holds, so none of them can proceed.

Related topics

• Deadlock: A cycle of threads each waiting on a lock another one holds, so none of them can proceed.