A new link type, BPF_LINK_TYPE_STRUCT_OPS, was added to attach
struct_ops to links. (226bc6ae6405) It would be helpful for users to
know which map is associated with the link.
The assumption was that every link is associated with a BPF program,
but this does not hold true for struct_ops. It would be better to
display map_id instead of prog_id for struct_ops links. However, some
tools may rely on the old assumption and need a prog_id displayed in
the link header line. By keeping the prog_id unchanged, an extra line
indicating the map_id is displayed.
Signed-off-by: Kui-Feng Lee <kuifeng@xxxxxxxx>
---
tools/bpf/bpftool/link.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c
index f985b79cca27..cb41a447ae3a 100644
--- a/tools/bpf/bpftool/link.c
+++ b/tools/bpf/bpftool/link.c
@@ -195,6 +195,10 @@ static int show_link_close_json(int fd, struct bpf_link_info *info)
info->netns.netns_ino);
show_link_attach_type_json(info->netns.attach_type, json_wtr);
break;
+ case BPF_LINK_TYPE_STRUCT_OPS:
+ jsonw_uint_field(json_wtr, "map_id",
+ info->struct_ops.map_id);
+ break;
default:
break;
}
@@ -301,6 +305,9 @@ static int show_link_close_plain(int fd, struct bpf_link_info *info)
printf("\n\tnetns_ino %u ", info->netns.netns_ino);
show_link_attach_type_plain(info->netns.attach_type);
break;
+ case BPF_LINK_TYPE_STRUCT_OPS:
+ printf("\n\tmap_id %u ", info->struct_ops.map_id);
+ break;
default:
break;
}
--
2.34.1
