Linux Adding New Control Since Its Splitlock Detector Is Wrecking Some Steam Play Games

Back in 2020 the Linux kernel added a split-lock detector since when they occur an atomic instruction spanning multiple cache lines and requiring a global bus lock is needed. This has an unfortunate heavy impact on the system and thus the detector was added to report it to the kernel log when a split-lock occurs. But earlier this year starting with Linux 5.19, kernel developers decided to "make life miserable" and intentionally slow down bad behaving apps that abuse split-locks. That in turn has caused problems for some games -- so far select Windows games running under Steam Play -- and thus a new kernel knob is being added to more easily adjust the behavior...