On Wed, Jun 5, 2024 at 10:51 AM Mykyta Yatsenko
<mykyta.yatsenko5@xxxxxxxxx> wrote:
>
> From: Mykyta Yatsenko <yatsenko@xxxxxxxx>
>
> Similarly to `bpf_program`, support `bpf_map` automatic attachment in
> `bpf_object__attach_skeleton`. Currently only struct_ops maps could be
> attached.
>
> Bpftool
> Code-generate links in skeleton struct for struct_ops maps.
> Similarly to `bpf_program_skeleton`, set links in `bpf_map_skeleton`.
>
> Libbpf
> Extending `bpf_map` with new `autoattach` field to support enabling or
> disabling autoattach functionality, introducing getter/setter for this
> field.
> Extending `bpf_object__(attach|detach)_skeleton` with
> attaching/detaching struct_ops maps.
>
> Signed-off-by: Mykyta Yatsenko <yatsenko@xxxxxxxx>
> ---
> tools/bpf/bpftool/gen.c | 36 +++++++++++++++++++---
> tools/lib/bpf/libbpf.c | 65 ++++++++++++++++++++++++++++++++++++++--
> tools/lib/bpf/libbpf.h | 20 +++++++++++++
> tools/lib/bpf/libbpf.map | 2 ++
> 4 files changed, 116 insertions(+), 7 deletions(-)
>
This looks great and finished (see minor nit below which I fixed up
while applying). I know you had a selftest ready, why didn't you
submit it? Please follow up with a selftest so we have this
functionality executed in our selftests. Thanks!
[...]
> + /* only struct_ops maps can be attached */
> + if (!bpf_map__is_struct_ops(map))
> + continue;
> + *link = bpf_map__attach_struct_ops(map);
> +
> + if (!*link) {
> + const int errcode = errno;
> +
> + pr_warn("struct_ops %s: failed to auto-attach: %d\n", bpf_map__name(map),
> + errcode);
> + return libbpf_err(-errcode);
there is err variable already in this function, I switched to using it here
> + }
> + }
> +
> return 0;
> }
>
[...]
