[$] The deadline scheduler and CPU idle states

As Rafael Wysocki conceded at the beginning of a session at the 2020 Power Management and Schedulingin the Linux Kernel summit (OSPM), the combination of the deadline scheduling class with CPU idle statesmight seem a little strange. Deadline scheduling is used in realtimesettings, where introducing latency by idling the CPU tends to be frownedupon. But there are reasons to think that these two technologies mightjust be made to work together.