On Mon, 2022-05-09 at 12:05 -0700, Andrii Nakryiko wrote:
> On Sat, May 7, 2022 at 8:21 PM Kui-Feng Lee <kuifeng@xxxxxx> wrote:
> >
> > Add a cookie field to the attributes of bpf_link_create().
> > Add bpf_program__attach_trace_opts() to attach a cookie to a link.
> >
> > Signed-off-by: Kui-Feng Lee <kuifeng@xxxxxx>
> > ---
> > tools/lib/bpf/bpf.c | 8 ++++++++
> > tools/lib/bpf/bpf.h | 3 +++
> > tools/lib/bpf/libbpf.c | 32 ++++++++++++++++++++++++++++++++
> > tools/lib/bpf/libbpf.h | 12 ++++++++++++
> > tools/lib/bpf/libbpf.map | 1 +
> > 5 files changed, 56 insertions(+)
> >
>
> I have a gripe with better code reuse, but that's internal change so
> we can do it in a follow up.
>
> Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
>
> > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> > index 73a5192defb3..df9be47d67bc 100644
> > --- a/tools/lib/bpf/libbpf.c
> > +++ b/tools/lib/bpf/libbpf.c
> > @@ -11440,6 +11440,38 @@ struct bpf_link
> > *bpf_program__attach_trace(const struct bpf_program *prog)
> > return bpf_program__attach_btf_id(prog);
> > }
> >
> > +struct bpf_link *bpf_program__attach_trace_opts(const struct
> > bpf_program *prog,
> > + const struct
> > bpf_trace_opts *opts)
>
> there is bpf_program__attach_btf_id() that does all of this except
> for
> the cookie. It would be nicer to extend bpf_program__attach_btf_id(),
> which won't break any API because it's an internal helper, add
> optional bpf_trace_opts to it and then just redirect
> bpf_program__attach_trace_opts() to bpf_program__attach_btf_id and
> update all the existing callers with just passing NULL for opts.
Fixed! I copied the code from bpf_program__attach_btf_id() for
testing, and forgot to refactor it.
>
> We can do that as a follow up, given your patch set seems to be
> pretty
> much ready to be landed.
>
> > +{
> > + char errmsg[STRERR_BUFSIZE];
> > + struct bpf_link *link;
> > + int prog_fd, pfd;
> > + LIBBPF_OPTS(bpf_link_create_opts, link_opts);
> > +
>
> [...]
