Re: [PATCH] libbpf: Fix up generation of bpf_helper_defs.h

Alexei Starovoitov
2019-11-28T01:53:24Z

On Wed, Nov 27, 2019 at 5:26 PM Arnaldo Carvalho de Melo
<arnaldo.melo@gmail.com> wrote:
>
> On November 27, 2019 10:20:17 PM GMT-03:00, Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote:
> >On Wed, Nov 27, 2019 at 5:17 PM Arnaldo Carvalho de Melo
> ><arnaldo.melo@gmail.com> wrote:
> >>
> >> On November 27, 2019 9:59:15 PM GMT-03:00, Alexei Starovoitov
> ><alexei.starovoitov@gmail.com> wrote:
> >> >On Wed, Nov 27, 2019 at 4:50 PM Arnaldo Carvalho de Melo
> >> ><arnaldo.melo@gmail.com> wrote:
> >> >>
> >> >> Take it as one, I think it's what should have been in the cset it
> >is
> >> >fixing, that way no breakage would have happened.
> >> >
> >> >Ok. I trimmed commit log and applied here:
> >>
> >>https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=1fd450f99272791df8ea8e1b0f5657678e118e90
> >> >
> >> >What about your other fix and my suggestion there?
> >> >(__u64) cast instead of PRI ?
> >> >We do this already in two places:
> >> >libbpf.c: shdr_idx, (__u64)sym->st_value);
> >> >libbpf.c: (__u64)sym.st_value,
> >GELF_ST_TYPE(sym.st_info),
> >>
> >>
> >> I'm using the smartphone now, but I thought you first suggested using
> >a cast to long, if you mean using %llu + cast to __u64, then should be
> >was ugly as using PRI, IOW, should work on both 64 bit and 32 bit. :-)
> >
> >Yes. I suggested (long) first, but then found two cases in libbpf that
> >solve this with (__u64),
> >so better to stick to that for consistency.
>
> If it's already being used elsewhere in lubbpf, it was tested already with the build containers and since nobody complained, go with it :-)

Ok.
Pushed this fix:
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=7c3977d1e80401b1a25efded698b05d60ee26e31
Likely will send PR for bpf tree to Dave tomorrow.