> I guess this would eliminate the problems caused by pm_idle.

Right.

...at least we can contain it inside process.c
where we still need to be able to handle halt/amd-bug/poll.
Probably I'll re-name it to better reflect its function,
say x86_default_idle, in this case.

> In that case I also think we need not implement a default
> driver (like the one I had done https://lkml.org/lkml/2011/3/22/154)
> to handle the case when acpi_idle and intel_idle may not register.

Right.

the stuff in process.c should handle the !cpuidle
and !CPU_IDLE cases, and in the typical case it will
handle idle during boot before cpuidle initializes.

> Additionally, we may not need to support multiple cpuidle driver registration
> as now there would be only acpi_idle and intel_idle
> and mechanism already exists to select between the two.

Right.

I think multiple driver registration is over-kill, though
I have no real opposition to it should a real need for it emerge.
The only need I could come up with is that it would save me
a reboot when I want to compare drivers -- but we should optimize
for real-world-use, not lab use, and simpler is better.

thanks,
Len Brown, Intel Open Source Technology Center