Re: [PATCH v3 bpf-next 02/10] bpftool: Dump the kernel symbol's module name

[Yafang Shao <laoar.shao@gmail.com>]

On Tue, Jun 13, 2023 at 9:41 PM Quentin Monnet <quentin@isovalent.com> wrote:
>
> 2023-06-12 15:16 UTC+0000 ~ Yafang Shao <laoar.shao@gmail.com>
> > If the kernel symbol is in a module, we will dump the module name as
> > well.
> >
> > Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
> > ---
> >  tools/bpf/bpftool/xlated_dumper.c | 6 +++++-
> >  tools/bpf/bpftool/xlated_dumper.h | 2 ++
> >  2 files changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/bpf/bpftool/xlated_dumper.c b/tools/bpf/bpftool/xlated_dumper.c
> > index da608e1..dd917f3 100644
> > --- a/tools/bpf/bpftool/xlated_dumper.c
> > +++ b/tools/bpf/bpftool/xlated_dumper.c
> > @@ -46,7 +46,11 @@ void kernel_syms_load(struct dump_data *dd)
> >               }
> >               dd->sym_mapping = tmp;
> >               sym = &dd->sym_mapping[dd->sym_count];
> > -             if (sscanf(buff, "%p %*c %s", &address, sym->name) != 2)
> > +
> > +             /* module is optional */
> > +             sym->module[0] = '\0';
> > +             if (sscanf(buff, "%p %*c %s %s", &address, sym->name,
> > +                 sym->module) < 2)
> >                       continue;
> >               sym->address = (unsigned long)address;
> >               if (!strcmp(sym->name, "__bpf_call_base")) {
> > diff --git a/tools/bpf/bpftool/xlated_dumper.h b/tools/bpf/bpftool/xlated_dumper.h
> > index 9a94637..5df8025 100644
> > --- a/tools/bpf/bpftool/xlated_dumper.h
> > +++ b/tools/bpf/bpftool/xlated_dumper.h
> > @@ -5,12 +5,14 @@
> >  #define __BPF_TOOL_XLATED_DUMPER_H
> >
> >  #define SYM_MAX_NAME 256
> > +#define MODULE_NAME_LEN      64
> >
> >  struct bpf_prog_linfo;
> >
> >  struct kernel_sym {
> >       unsigned long address;
> >       char name[SYM_MAX_NAME];
> > +     char module[MODULE_NAME_LEN];
>
> Nit: MODULE_MAX_NAME would be more consistent and would make more sense
> to me? And it would avoid confusion with MODULE_NAME_LEN from kernel,
> which doesn't have the same value.

Will use MODULE_MAX_NAME instead.

-- 
Regards
Yafang