The Linux kernel contains a full counting semaphore implementation. Given a semaphore, a call to down() will sleep until the semaphore contains a positive value, decrement that value, and return.

Proper locking can be tough—real tough. Improper locking can result in random crashes and other oddities. Poorly designed locking can result in code that is hard to read, performs poorly and makes ...

The kernel's handling of concurrency has changed a lot over the years. In 2023, a kernel developer's toolkit includes tools like completions, highly optimized mutexes, and a variety of lockless ...