What happens if two process in different processors try to acquire the lock at EXACTLY same time

Question

Ok, so I am reading about synchronization, and I read through various algorithms such as spinlocks, semaphores, and mutex to avoid race condition.

However, these alg

Answer 1

I strongly recommend Curt Schimmel's UNIX® Systems for Modern Architectures: Symmetric Multiprocessing and Caching for Kernel Programmers. Different hardware architectures provide different low-level tools for synchronizing access to data, including some architectures with very nearly no help. Schimmel's book provides algorithms that can work even on those architectures.

I wish I could easily locate my copy to summarize the contents.