Re: [RFC PATCH] preempt: Add a generic function to return the preemption string.

[Peter Zijlstra]

On Thu, Jan 09, 2025 at 03:41:24PM +0100, Sebastian Andrzej Siewior wrote:
> On 2025-01-09 15:37:01 [+0100], Peter Zijlstra wrote:
> > Upgrade brain. Also the proposed thing was just plain wrong.
> 
> Was it?

Yes, things like:

> +             if (preempt_model_voluntary())
> +                     return "VOLUNTARY+LAZY";
> +             if (preempt_model_none())
> +                     return "NONE+LAZY";

don't exist and make no sense.

> For the !DYNAMIC case everything should be optimized away except
> for the current case.
> Let me try your thing to see what is different…

For the various cases it was supposed to print something like so:

RT+DYN:	 PREEMPT_{RT,(dyn_mode)}
RT+LAZY: PREEMPT_{RT,LAZY}
RT+FULL: PREEMPT_RT

DYN:       PREEMPT_(dyn_mode)
FULL:      PREEMPT
LAZY:      PREEMPT_LAZY
VOLUNTARY: VOLUNTARY
NONE:      NONE