Re: [PATCH v2 1/2] tools/resolve_btfids: Add --fatal-warnings option

[Andrii Nakryiko]

On Tue, Nov 26, 2024 at 1:17 PM Thomas Weißschuh <linux@xxxxxxxxxxxxxx> wrote:
>
> Currently warnings emitted by resolve_btfids are buried in the build log
> and are slipping into mainline frequently.
> Add an option to elevate warnings to hard errors so the CI bots can
> catch any new warnings.
>
> Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
>  tools/bpf/resolve_btfids/main.c | 12 ++++++++++--
>  1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c
> index bd9f960bce3d5b74dc34159b35af1e0b33524d2d..571d29d2da97fea75e5f9c544a95b9ac65f9e579 100644
> --- a/tools/bpf/resolve_btfids/main.c
> +++ b/tools/bpf/resolve_btfids/main.c
> @@ -141,6 +141,7 @@ struct object {
>  };
>
>  static int verbose;
> +static int warnings;
>
>  static int eprintf(int level, int var, const char *fmt, ...)
>  {
> @@ -604,6 +605,7 @@ static int symbols_resolve(struct object *obj)
>                         if (id->id) {
>                                 pr_info("WARN: multiple IDs found for '%s': %d, %d - using %d\n",
>                                         str, id->id, type_id, id->id);
> +                               warnings++;
>                         } else {
>                                 id->id = type_id;
>                                 (*nr)--;
> @@ -625,8 +627,10 @@ static int id_patch(struct object *obj, struct btf_id *id)
>         int i;
>
>         /* For set, set8, id->id may be 0 */
> -       if (!id->id && !id->is_set && !id->is_set8)
> +       if (!id->id && !id->is_set && !id->is_set8) {
>                 pr_err("WARN: resolve_btfids: unresolved symbol %s\n", id->name);
> +               warnings++;
> +       }
>
>         for (i = 0; i < id->addr_cnt; i++) {
>                 unsigned long addr = id->addr[i];
> @@ -782,6 +786,7 @@ int main(int argc, const char **argv)
>                 .funcs    = RB_ROOT,
>                 .sets     = RB_ROOT,
>         };
> +       bool fatal_warnings = false;
>         struct option btfid_options[] = {
>                 OPT_INCR('v', "verbose", &verbose,
>                          "be more verbose (show errors, etc)"),
> @@ -789,6 +794,8 @@ int main(int argc, const char **argv)
>                            "BTF data"),
>                 OPT_STRING('b', "btf_base", &obj.base_btf_path, "file",
>                            "path of file providing base BTF"),
> +               OPT_BOOLEAN(0, "fatal-warnings", &fatal_warnings,
> +                           "turn warnings into errors"),

We are mixing naming styles here: we have "btf_base" with underscore
separator, and you are adding "fatal-warnings" with dash separator. I
personally like dashes, but whichever way we should stay consistent.
So let's fix it, otherwise it looks a bit sloppy.

Please also use [PATCH bpf-next v3] subject prefix to make it explicit
that this should go through bpf-next tree.

pw-bot: cr

>                 OPT_END()
>         };
>         int err = -1;
> @@ -823,7 +830,8 @@ int main(int argc, const char **argv)
>         if (symbols_patch(&obj))
>                 goto out;
>
> -       err = 0;
> +       if (!(fatal_warnings && warnings))
> +               err = 0;

nit: just

if (!fatal_warnings)
    err = 0;

?

>  out:
>         if (obj.efile.elf) {
>                 elf_end(obj.efile.elf);
>
> --
> 2.47.1
>