Sure. But another way of seeing it is: SCHED_FIFO/RR introduces the
possibility of deadlocks and makes it seem more reasonable to introduce
other scheduling classes that are not any worse. So the original
mistake has a snowball effect. The problem is that SCHED_RR/FIFO is
incorrectly implemented as the highest priority class. What is needed
is a priority class switch that makes sure SCHED_OTHER gets some
percentage of the cpu time. As I understand the POSIX specs, there is
no specification of the interaction between scheduling policies. So
it is POSIX compliant to give some time to SCHED_OTHER processes even
when SCHED_RR processes are ready to run.
>Which is why I support moving !SCHED_OTHER processes to
> SCHED_OTHER when they call schedule(), and moving them back when
> schedule() returns.
Doesn't that defeat the purpose of the soft-rt? There is no
point in being SCHED_RR only when you own the processor.
Or maybe I misunderstand your idea?
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