Re: [PATCH bpf-next v1] bpf,arena: Rename the kfunc set variable

From: Andrii Nakryiko
Date: Tue May 07 2024 - 17:21:00 EST


On Tue, May 7, 2024 at 1:42 PM Alexei Starovoitov
<alexei.starovoitov@xxxxxxxxx> wrote:
>
> On Tue, May 7, 2024 at 9:43 AM Andrii Nakryiko
> <andrii.nakryiko@xxxxxxxxx> wrote:
> >
> > On Tue, May 7, 2024 at 7:36 AM Alexei Starovoitov
> > <alexei.starovoitov@xxxxxxxxx> wrote:
> > >
> > > On Mon, May 6, 2024 at 7:46 PM Haiyue Wang <haiyue.wang@intelcom> wrote:
> > > >
> > > > Rename the kfunc set variable to specify the 'arena' function scope,
> > > > although the 'UNSPEC' type BPF program is mapped to 'COMMON' hook.
> > > >
> > > > And there is 'common_kfunc_set' defined for real 'common' function in
> > > > file 'kernel/bpf/helpers.c'.
> > >
> > > I think common_kfunc_set is a better name to describe that these
> > > two kfuncs are in a common category.
> > > BPF_PROG_TYPE_UNSPEC is a lot less obvious.
> > >
> > > There are two static common_kfunc_set in helpers.c and arena.c
> > > and that's fine.
> >
> > it is actually confusing when reading/grepping code, though, so why
>
> What's the confusion? Same name static var in different files?

Not in general, but in this case it's arena-specific kfuncs for all
program types, and it's initialized with &arena_kfuncs, so it would be
matching to have some "arena" mention in the name. But it's minor,
let's keep it.

> There are tons of such cases in the kernel src tree.
>
> > not have arena_common_kfunc_set and whatever the meaningful
> > "qualifier" name for the other one?
>
> arena_common_kfunc_set is certainly better than arena_kfunc_set,
> but I don't like to make the precedent to start renaming static vars
> because they have the same name.
>
> > >
> > > pw-bot: cr