On Fri, Jun 02, 2023 at 08:52:39AM +0000, Yafang Shao wrote:
> Show the exposed perf_event link info in bpftool. The result as follows,
>
> $ bpftool link show
> 1: perf_event prog 5
> func kernel_clone addr ffffffffb40bc310 offset 0
> bpf_cookie 0
> pids trace(9726)
> $ bpftool link show -j
> [{"id":1,"type":"perf_event","prog_id":5,"func":"kernel_clone","addr":18446744072435254032,"offset":0,"bpf_cookie":0,"pids":[{"pid":9726,"comm":"trace"}]}]
>
> Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
> ---
> tools/bpf/bpftool/link.c | 21 ++++++++++++++++++++-
> 1 file changed, 20 insertions(+), 1 deletion(-)
>
> diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c
> index 3b00c07..045f59f 100644
> --- a/tools/bpf/bpftool/link.c
> +++ b/tools/bpf/bpftool/link.c
> @@ -280,6 +280,12 @@ static int show_link_close_json(int fd, struct bpf_link_info *info)
> kernel_syms_show(addrs, info->kprobe_multi.count, 0);
> jsonw_end_array(json_wtr);
> break;
> + case BPF_LINK_TYPE_PERF_EVENT:
> + jsonw_string_field(json_wtr, "func",
> + u64_to_ptr(info->perf_event.name));
> + jsonw_uint_field(json_wtr, "addr", info->perf_event.addr);
> + jsonw_uint_field(json_wtr, "offset", info->perf_event.offset);
> + break;
> default:
> break;
> }
> @@ -416,7 +422,7 @@ void netfilter_dump_plain(const struct bpf_link_info *info)
> static int show_link_close_plain(int fd, struct bpf_link_info *info)
> {
> struct bpf_prog_info prog_info;
> - const char *prog_type_str;
> + const char *prog_type_str, *buf;
> int err;
>
> show_link_header_plain(info);
> @@ -472,6 +478,12 @@ static int show_link_close_plain(int fd, struct bpf_link_info *info)
> addrs = (const __u64 *)u64_to_ptr(info->kprobe_multi.addrs);
> kernel_syms_show(addrs, cnt, indent);
> break;
> + case BPF_LINK_TYPE_PERF_EVENT:
> + buf = (const char *)u64_to_ptr(info->perf_event.name);
> + if (buf[0] != '\0' || info->perf_event.addr)
> + printf("\n\tfunc %s addr %llx offset %d ", buf,
> + info->perf_event.addr, info->perf_event.offset);
Let's print the name here as well?
