Em Tue, Nov 23, 2021 at 10:32:18AM -0800, Andrii Nakryiko escreveu:
> On Mon, Nov 22, 2021 at 8:56 PM Yonghong Song <yhs@xxxxxx> wrote:
> >
> > btf_type_tag is a new llvm type attribute which is used similar
> > to kernel __user/__rcu attributes. The format of btf_type_tag looks like
> > __attribute__((btf_type_tag("tag1")))
> > For the case where the attribute applied to a pointee like
> > #define __tag1 __attribute__((btf_type_tag("tag1")))
> > #define __tag2 __attribute__((btf_type_tag("tag2")))
> > int __tag1 * __tag1 __tag2 *g;
> > the information will be encoded in dwarf.
> >
> > In BTF, the attribute is encoded as a new kind
> > BTF_KIND_TYPE_TAG and latest bpf-next supports it.
> >
> > The patch added support in pahole, specifically
> > converts llvm dwarf btf_type_tag attributes to
> > BTF types. Please see individual patches for details.
> >
> > Changelog:
> > v1 -> v2:
> > - reorg an if condition to reduce nesting level.
> > - add more comments to explain how to chain type tag types.
> >
> > Yonghong Song (4):
> > libbpf: sync with latest libbpf repo
> > dutil: move DW_TAG_LLVM_annotation definition to dutil.h
> > dwarf_loader: support btf_type_tag attribute
> > btf_encoder: support btf_type_tag attribute
> >
>
> I thought that v1 was already applied, but either way LGTM. I'm not
To the next branch, and the libbpf pahole CI is failing, since a few
days, can you please take a look?
> super familiar with the DWARF loader parts, so I mostly just read it
> very superficially :)
I replaced the patches that changed, re-added the S-o-B for Yonghong and
tested it with llvm-project HEAD.
> Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Adding it to the csets.
Thanks!
- Arnaldo
>
> > btf_encoder.c | 7 +++
> > dutil.h | 4 ++
> > dwarf_loader.c | 140 ++++++++++++++++++++++++++++++++++++++++++++++---
> > dwarves.h | 38 +++++++++++++-
> > lib/bpf | 2 +-
> > pahole.c | 8 +++
> > 6 files changed, 190 insertions(+), 9 deletions(-)
> >
> > --
> > 2.30.2
> >
--
- Arnaldo
