Re: [PATCH bpf-next 1/3] bpf: Add cookie to raw_tp bpf_link_info

[Tao Chen]

在 2025/5/31 16:30, Jiri Olsa 写道:
> On Fri, May 30, 2025 at 12:57:57AM +0800, Tao Chen wrote:
> > After commit 68ca5d4eebb8 ("bpf: support BPF cookie in raw tracepoint
> > (raw_tp, tp_btf) programs"), we can show the cookie in bpf_link_info
> > like kprobe etc.
> >
> > Signed-off-by: Tao Chen <chen.dylane@xxxxxxxxx>
> > ---
> >   include/uapi/linux/bpf.h       | 1 +
> >   kernel/bpf/syscall.c           | 1 +
> >   tools/include/uapi/linux/bpf.h | 1 +
> >   3 files changed, 3 insertions(+)
> >
> > diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> > index 07ee73cdf9..7d0ad5c2b6 100644
> > --- a/include/uapi/linux/bpf.h
> > +++ b/include/uapi/linux/bpf.h
> > @@ -6644,6 +6644,7 @@ struct bpf_link_info {
> >   		struct {
> >   			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
> >   			__u32 tp_name_len;     /* in/out: tp_name buffer len */
>
> there's hole now in here, let's add something like
>
>    __u32 reserved;

Sounds good, i will add it in v2, thanks.

> jirka
>
>
> > +			__u64 cookie;
> >   		} raw_tracepoint;
> >   		struct {
> >   			__u32 attach_type;
> > diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> > index 9794446bc8..1c3dbe44ac 100644
> > --- a/kernel/bpf/syscall.c
> > +++ b/kernel/bpf/syscall.c
> > @@ -3687,6 +3687,7 @@ static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
> >   		return -EINVAL;
> >   
> >   	info->raw_tracepoint.tp_name_len = tp_len + 1;
> > +	info->raw_tracepoint.cookie = raw_tp_link->cookie;
> >   
> >   	if (!ubuf)
> >   		return 0;
> > diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
> > index 07ee73cdf9..7d0ad5c2b6 100644
> > --- a/tools/include/uapi/linux/bpf.h
> > +++ b/tools/include/uapi/linux/bpf.h
> > @@ -6644,6 +6644,7 @@ struct bpf_link_info {
> >   		struct {
> >   			__aligned_u64 tp_name; /* in/out: tp_name buffer ptr */
> >   			__u32 tp_name_len;     /* in/out: tp_name buffer len */
> > +			__u64 cookie;
> >   		} raw_tracepoint;
> >   		struct {
> >   			__u32 attach_type;
> > --
> > 2.43.0


--
Best Regards
Tao Chen