bpf: Add cookie in fdinfo for tracing

Add cookie in fdinfo for tracing, the info as follows:

link_type:	tracing
link_id:	6
prog_tag:	9dfdf8ef453843bf
prog_id:	35
attach_type:	25
target_obj_id:	1
target_btf_id:	60355
cookie:	9007199254740992

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250606165818.3394397-4-chen.dylane@linux.dev

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 85e080c3333df7a85b0ccb9cfd9fcef07a35ee77..185cf662451d7dad92d645c30121067f4c4bf8e4 100644 (file)
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3403,10 +3403,12 @@ static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
        seq_printf(seq,
                   "attach_type:\t%d\n"
                   "target_obj_id:\t%u\n"
-                  "target_btf_id:\t%u\n",
+                  "target_btf_id:\t%u\n"
+                  "cookie:\t%llu\n",
                   tr_link->attach_type,
                   target_obj_id,
-                  target_btf_id);
+                  target_btf_id,
+                  tr_link->link.cookie);
 }
 
 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,