On Sat, Jun 3, 2023 at 6:20 AM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> On Fri, Jun 2, 2023 at 1:52 AM Yafang Shao <laoar.shao@xxxxxxxxx> wrote:
> >
> > By adding support for ->fill_link_info to the perf_event link, users will
> > be able to inspect it using `bpftool link show`. While users can currently
> > access this information via `bpftool perf show`, consolidating the link
> > information for all link types in one place would be more convenient.
> >
> > Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
> > ---
> > include/uapi/linux/bpf.h | 6 ++++++
> > kernel/bpf/syscall.c | 45 ++++++++++++++++++++++++++++++++++++++++++
> > tools/include/uapi/linux/bpf.h | 6 ++++++
> > 3 files changed, 57 insertions(+)
> >
> > diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> > index 22c8168..87ecf8b 100644
> > --- a/include/uapi/linux/bpf.h
> > +++ b/include/uapi/linux/bpf.h
> > @@ -6442,6 +6442,12 @@ struct bpf_link_info {
> > __u64 addrs;
> > __u32 count;
> > } kprobe_multi;
> > + struct {
> > + __aligned_u64 name; /* in/out: symbol name buffer ptr */
> > + __u64 addr;
> > + __u32 name_len;
> > + __u32 offset;
> > + } perf_event;
>
> perf_event link could be:
>
> a) uprobe
> b) kprobe
> c) tracepoint
> d) generic perf_event (e.g., cpu_cycles)
>
> This interface doesn't make it very clear which one it is. And what's
> "name" for cpu_cycles event? What is the name for uprobe? Let's
> actually document this, otherwise it's hard to understand how this
> information can be interpreted...
Agreed. It would be better to have a document on it. I will do it.
--
Regards
Yafang
