Jisheng Zhang [off-list ref] writes:

On Tue, Nov 18, 2025 at 11:03:41PM +0100, Robert Jarzmik wrote:

hmm, each controller adds 16bytes, then even on 100 controller 
platforms
1600bytes. 1600 Bytes/64MB ~= 0.238%. it's trival. And is there 
such platform?

Yes, actually most of them have around 64MB, at least the pxa25x 
and pxa27x.
The pxa3xx might have more (thing 128MB, maybe 256MB).
There are very old platforms, we're in 2003/2004 there ...

From another side, recently UP support is removed from the core 
sched,
that removing adds more .text and .data overhead, so if the 
users really
care about this kind of 16bytes, it means he(she) can't afford 
even the
16Bytes overhead, then I bet he(she) the always SMP in core 
sched, so
why not stick with the old kernel? What do you think?

I think I would go with Andy's proposal, decouple the changes :
 - keep your changes in the PM callbaks
 - remove your change (put back the ifdef) in the data structure

Cheers.

--
Robert