Re: [PATCH v2 00/18] sysctl: constify sysctl ctl_tables

From: Julia Lawall
Date: Fri Dec 15 2023 - 12:05:22 EST




On Fri, 15 Dec 2023, Thomas Weißschuh wrote:

> On 2023-12-12 23:51:30-0800, Luis Chamberlain wrote:
> > On Tue, Dec 12, 2023 at 10:09:30AM +0100, Joel Granados wrote:
> > > My idea was to do something similar to your originl RFC, where you have
> > > an temporary proc_handler something like proc_hdlr_const (we would need
> > > to work on the name) and move each subsystem to the new handler while
> > > the others stay with the non-const one. At the end, the old proc_handler
> > > function name would disapear and would be completely replaced by the new
> > > proc_hdlr_const.
> > >
> > > This is of course extra work and might not be worth it if you don't get
> > > negative feedback related to tree-wide changes. Therefore I stick to my
> > > previous suggestion. Send the big tree-wide patches and only explore
> > > this option if someone screams.
> >
> > I think we can do better, can't we just increase confidence in that we
> > don't *need* muttable ctl_cables with something like smatch or
> > coccinelle so that we can just make them const?
>
> The fact that the code compiles should be enough, no?
> Any funky casting that would trick the compiler to accept it would
> probably also confuse any other tool.

I don't know the context, but the fact that a particular file compiles
doesn't mean that all of the lines in the file have been subjected to the
compiler, due to ifdefs.

julia

>
> > Seems like a noble endeavor for us to generalize.
> >
> > Then we just breeze through by first fixing those that *are* using
> > mutable tables by having it just de-register and then re-register
> > new tables if they need to be changed, and then a new series is sent
> > once we fix all those muttable tables.
>
> Ack. But I think the actual constification should really only be started
> after the first series for the infrastructure is in.
>
> Thomas
>