Show the target bpf prog info in the fdinfo. $ cat /proc/self/fdinfo/13 pos: 0 flags: 02000000 mnt_id: 18 ino: 1045 link_type: tracing_multi link_id: 9 prog_tag: 9a7f9e3ab6f138ab prog_id: 25 attach_type: 61 cnt: 2 prog-id btf-id cookie func 21 4 16706819 target_1 22 5 16706819 target_2
Signed-off-by: Leon Hwang <[email protected]> --- kernel/trace/bpf_trace.c | 30 +++++++++++++++++++++++++----- 1 file changed, 25 insertions(+), 5 deletions(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index a805a5b73303..80928401830c 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3759,26 +3759,46 @@ static int bpf_tracing_multi_link_fill_link_info(const struct bpf_link *link, } #ifdef CONFIG_PROC_FS +static const char *bpf_prog_func_name(struct bpf_prog *prog, u32 btf_id) +{ + const struct btf *btf = prog->aux->btf; + const struct btf_type *t; + + t = btf_type_by_id(btf, btf_id); + if (!t || !btf_type_is_func(t)) + return ""; + + return btf_name_by_offset(btf, t->name_off); +} + static void bpf_tracing_multi_show_fdinfo(const struct bpf_link *link, struct seq_file *seq) { struct bpf_tracing_multi_link *tr_link = container_of(link, struct bpf_tracing_multi_link, link); bool has_cookies = !!tr_link->cookies; + bool has_progs = !!tr_link->progs; seq_printf(seq, "attach_type:\t%u\n", tr_link->link.attach_type); seq_printf(seq, "cnt:\t%u\n", tr_link->nodes_cnt); - seq_printf(seq, "%s\t %s\t %s\t %s\n", "obj-id", "btf-id", "cookie", "func"); + seq_printf(seq, "%s\t %s\t %s\t %s\n", has_progs ? "prog-id" : "obj-id", "btf-id", "cookie", + "func"); for (int i = 0; i < tr_link->nodes_cnt; i++) { struct bpf_tracing_multi_node *mnode = &tr_link->nodes[i]; + u64 cookie = has_cookies ? tr_link->cookies[i] : 0; u32 btf_id, obj_id; bpf_trampoline_unpack_key(mnode->trampoline->key, &obj_id, &btf_id); - seq_printf(seq, "%u\t %u\t %llu\t %pS\n", - obj_id, btf_id, - has_cookies ? tr_link->cookies[i] : 0, - (void *) mnode->trampoline->ip); + btf_id = has_progs ? (u32) mnode->trampoline->key : btf_id; + if (has_progs) + seq_printf(seq, "%u\t %u\t %llu\t %s\n", + obj_id, btf_id, cookie, + bpf_prog_func_name(tr_link->progs[i], btf_id)); + else + seq_printf(seq, "%u\t %u\t %llu\t %pS\n", + obj_id, btf_id, cookie, + (void *) mnode->trampoline->ip); cond_resched(); } -- 2.55.0
