[$] Nested bottom-half locking for realtime kernels
17 juin 2024 à 14:27
Software-interrupt handlers (also called "bottom halves") have a long
history in the Linux kernel; for much of that history, developers have
wished that they could go away. One of their unfortunate characteristics
is that they can add unexpected latency to the execution of unrelated
processes; this problem is felt especially acutely in the
realtime-preemption community. The solution adopted there has created
problems of its own, though; in response Sebastian Andrzej Siewior is proposing
a new locking mechanism for realtime builds of the kernel that may have
benefits for non-realtime users as well.