The target_btf_id can help us understand which kernel function is
linked by a tracing prog. The target_btf_id and target_obj_id have
already been exposed to userspace, so we just need to show them.
The result as follows,
$ cat /proc/10673/fdinfo/10
pos: 0
flags:
02000000
mnt_id: 15
ino: 2094
link_type: tracing
link_id: 2
prog_tag:
a04f5eef06a7f555
prog_id: 13
attach_type: 24
target_obj_id: 1
target_btf_id: 13964
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230517103126.68372-2-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
{
struct bpf_tracing_link *tr_link =
container_of(link, struct bpf_tracing_link, link.link);
+ u32 target_btf_id, target_obj_id;
+ bpf_trampoline_unpack_key(tr_link->trampoline->key,
+ &target_obj_id, &target_btf_id);
seq_printf(seq,
- "attach_type:\t%d\n",
- tr_link->attach_type);
+ "attach_type:\t%d\n"
+ "target_obj_id:\t%u\n"
+ "target_btf_id:\t%u\n",
+ tr_link->attach_type,
+ target_obj_id,
+ target_btf_id);
}
static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,