Re: [PATCH v4 1/9] sched: Add a generic function to return the preemption string.

[Ingo Molnar <mingo@kernel.org>]

* Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:

> On 2025-03-17 10:12:31 [+0100], Ingo Molnar wrote:
> > 
> > * Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
> > 
> > > On 2025-03-16 12:15:47 [+0100], Ingo Molnar wrote:
> > > > 
> > > > * Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
> > > > 
> > > > > +const char *preempt_modes[] = {
> > > > > +	"none", "voluntary", "full", "lazy", NULL,
> > > > > +};
> > > > 
> > > > > +	/* Count entries in NULL terminated preempt_modes */
> > > > > +	for (j = 0; preempt_modes[j]; j++)
> > > > > +		;
> > > > 
> > > > I'm pretty sure the build-time ARRAY_SIZE() primitive is superior here. ;-)
> > > 
> > > It would be but it is not an option.
> > > That array is defined in core.c where it is "always" required while
> > > debug.c needs it optionally. core.c is its one compile unit while
> > > debug.c is included by build_utility.c. So I don't see how this can work
> > > unless we shift things:
> > 
> > Why not have it all in debug.c?
> 
> The debug.c include is behind CONFIG_SCHED_DEBUG. This needs to be moved
> into debug.c itself so that code can be added regardless of
> CONFIG_SCHED_DEBUG. It is not only sched-debug after that.

Yeah, that's a valid concern.

The thing is, CONFIG_SCHED_DEBUG is mostly meaningless these days - all 
major distributions enable it because of the statistics are useful for 
system administration, tooling and general software development.

So we should enable it permanently and remove the #ifdeffery. I'll send 
out a series to do so soon.

Thanks,

	Ingo