Lecture
This lecture discusses locking primitives essential for avoiding race conditions in multithreaded programming. It begins by explaining the issues with uncontrolled thread scheduling and the resulting race conditions that can affect program correctness. The instructor emphasizes the need for atomic operations to ensure that critical sections of code are executed without interference from other threads. The concept of mutual exclusion is introduced, highlighting how locks can be used to protect critical sections. The lecture covers various types of locks, including interruptible locks and spin locks, detailing their implementations and limitations. The instructor also explains the importance of hardware support for atomic operations, introducing primitives like test-and-set and compare-and-swap. These hardware instructions help implement locking mechanisms that ensure mutual exclusion but may lead to fairness issues, such as starvation. The lecture concludes by discussing the inefficiencies of spin locks and the importance of choosing appropriate locking strategies in concurrent programming.