Re: [PATCH v4 8/8] arm,arm64,drivers: add a prefix to drivers arch_topology interfaces

From: Greg KH
Date: Fri May 26 2017 - 14:36:50 EST


On Fri, May 26, 2017 at 11:10:32AM +0100, Juri Lelli wrote:
> Hi,
>
> On 25/05/17 15:18, Greg KH wrote:
> > On Thu, Apr 20, 2017 at 03:43:16PM +0100, Juri Lelli wrote:
> > > Now that some functions that deal with arch topology information live
> > > under drivers, there is a clash of naming that might create confusion.
> > >
> > > Tidy things up by creating a drivers namespace for interfaces used by
> > > arch code; achieve this by prepending a 'atd_' (arch topology driver)
> > > prefix to driver interfaces.
> >
> > No one knows, nor will they ever remember, what "atd_" means :(
> >
> > Naming is hard, I know, here's my suggestion:
> >
> > > diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h
> > > index 4edae9fe8cdd..e25458d7ee9a 100644
> > > --- a/include/linux/arch_topology.h
> > > +++ b/include/linux/arch_topology.h
> > > @@ -4,14 +4,14 @@
> > > #ifndef _LINUX_ARCH_TOPOLOGY_H_
> > > #define _LINUX_ARCH_TOPOLOGY_H_
> > >
> > > -void normalize_cpu_capacity(void);
> > > +void atd_normalize_cpu_capacity(void);
> >
> > arch_cpu_normalize_capacity();
> > or
> > cpu_normalize_capacity();
> >
> > Why do you care if this is "arch" or not, of course it's arch-specific
> > in a way, right?
> >
> > >
> > > struct device_node;
> > > -int parse_cpu_capacity(struct device_node *cpu_node, int cpu);
> > > +int atd_parse_cpu_capacity(struct device_node *cpu_node, int cpu);
> >
> > cpu_parse_capacity();
> >
> > > struct sched_domain;
> > > -unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu);
> > > +unsigned long atd_scale_cpu_capacity(struct sched_domain *sd, int cpu);
> >
> > cpu_scale_capacity();
> >
> > > -void set_capacity_scale(unsigned int cpu, unsigned long capacity);
> > > +void atd_set_capacity_scale(unsigned int cpu, unsigned long capacity);
> >
> > wait, where did the cpu go? This doesn't make much sense, these are all
> > "capacity" issues, right? If so, then these should be:
> > capacity_normalize_cpu()
> > capacity_parse_cpu()
> > capacity_scale_cpu()
> > capacity_set_scale()
> >
> > But this is all really topology stuff, right? Why use "capacity" at
> > all:
> > topology_normalize_cpu()
> > topology_parse_cpu()
> > topology_scale_cpu()
> > topology_set_scale()
> > ?
> >
> > It's always best to put the "subsystem" name first, we have a bad
> > history of getting this wrong in the past by putting the verb first, not
> > the noun.
> >
>
> topology_ works for me. However, I'd keep "capacity" in the names, as we
> might need to topology_normalize_cpu_somethingelse() (etc.) in the
> future?

Worry about the future, in the future. Change the names then, _IF_ it
becomes an issue. Try to be short and simple please.

> Updated patch follows. I kept Catalin and Russell's acks as I only
> renamed the functions, please shout if that's not OK.
>
> Greg, if you are fine with this approach, do you still want a complete
> v5 of the set or can you pick this up?

Am I the one who is supposed to take all of these arm-specific patches?
If so, that's fine, but I need to have acks from the arm maintainers...

Oh, and drop "capacity" please :)

thanks,

greg k-h