Re: [PATCH bpf-next v5 4/6] bpftool: generated shadow variables for struct_ops maps.

[Kui-Feng Lee <sinquersw@gmail.com>]

Will fix most of issues.

On 2/28/24 10:25, Andrii Nakryiko wrote:
> On Mon, Feb 26, 2024 at 5:04 PM Kui-Feng Lee <thinker.li@gmail.com> wrote:
>>
>> + * type. Accessing them through the generated names may unintentionally
>> + * corrupt data.
>> + */
>> +static int gen_st_ops_shadow_type(struct btf *btf, const char *ident,
>> +                                 const struct bpf_map *map)
>> +{
>> +       int err;
>> +
>> +       printf("\t\tstruct {\n");
> 
> would it be useful to still name this type? E.g., if it is `struct
> bpf_struct_ops_tcp_congestion_ops in vmlinux BTF` we can name this one
> as <skeleton-name>__bpf_struct_ops_tcp_congestion_ops. We have a
> similar pattern for bss/data/rodata sections, having names is useful.

If a user defines several struct_ops maps with the same name and type in
different files, it can cause name conflicts. Unless we also prefix the
name with the name of the skeleton. I am not sure if it is a good idea
to generate such long names. If a user want to refer to the type, he
still can use typeof(). WDYT?

> 
>> +
>> +       err = walk_st_ops_shadow_vars(btf, ident, map);
>> +       if (err)
>> +               return err;
>> +
>> +       printf("\t\t} *%s;\n", ident);
>> +
>> +       return 0;
>> +}
>> +