David Gwynne <david@gwynne.id.au> wrote:

> we just went through an effort to shrink kernel code to help the install media fit. it seems a bit ungrateful to use those bytes again for something that's generally only going to be used for performance monitoring.

Nope, that's not a good reason at all.  Prefer not to trade tons of cpp
conditionals all over the place, for having more very different kernel
execution behaviours.

OTOH, it will take some time to get this into all the architectures.  Once
that's done, this should become a baseline feature.  Only then can MI code
call it.   Providing it behind an #ifdef means that it should not be called
from inside an #ifdef.