Solaris™ Internals: Core Kernel Components

3.5. Mutex Locks

Mutual exclusion, or mutex locks, are the most common type of synchronization primitive used in the kernel. Mutex locks serialize access to critical data, when a kernel thread must acquire the mutex specific to the data region being protected before it can read or write the data. The thread is the lock owner while it is holding the lock, and the thread must release the lock when it has finished working in the protected region so other threads can acquire the lock for access to the protected data.

3.5.1. Overview

If a thread attempts to acquire a mutex lock that is being held, it can basically do one of two things: it can spin or it can block. Spinning means the thread enters a tight loop, attempting to acquire the lock in each ...