Show kprobe_multi link info with fdinfo, the info as follows:
link_type: kprobe_multi
link_id: 3
prog_tag: e8225cbcc9cdffef
prog_id: 29
type: kprobe_multi
kprobe_cnt: 8
missed: 0
func: bpf_fentry_test1+0x0/0x20
cookie: 1
func: bpf_fentry_test2+0x0/0x20
cookie: 7
func: bpf_fentry_test3+0x0/0x20
cookie: 2
func: bpf_fentry_test4+0x0/0x20
cookie: 3
func: bpf_fentry_test5+0x0/0x20
cookie: 4
func: bpf_fentry_test6+0x0/0x20
cookie: 5
func: bpf_fentry_test7+0x0/0x20
cookie: 6
func: bpf_fentry_test8+0x0/0x10
cookie: 8
Signed-off-by: Tao Chen <chen.dylane@xxxxxxxxx>
---
kernel/trace/bpf_trace.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 9a8ca8a8e2b..d060c61e4e4 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2623,10 +2623,43 @@ static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link,
return err;
}
+#ifdef CONFIG_PROC_FS
+static void bpf_kprobe_multi_show_fdinfo(const struct bpf_link *link,
+ struct seq_file *seq)
+{
+ struct bpf_kprobe_multi_link *kmulti_link;
+ char sym[KSYM_NAME_LEN];
+
+ kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
+
+ seq_printf(seq,
+ "type:\t%s\n"
+ "kprobe_cnt:\t%u\n"
+ "missed:\t%lu\n",
+ kmulti_link->flags == BPF_F_KPROBE_MULTI_RETURN ? "kretprobe_multi" :
+ "kprobe_multi",
+ kmulti_link->cnt,
+ kmulti_link->fp.nmissed);
+
+ for (int i = 0; i < kmulti_link->cnt; i++) {
+ sprint_symbol(sym, kmulti_link->addrs[i]);
+ seq_printf(seq,
+ "func:\t%s\n"
+ "cookie:\t%llu\n",
+ sym,
+ kmulti_link->cookies[i]
+ );
+ }
+}
+#endif
+
static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
.release = bpf_kprobe_multi_link_release,
.dealloc_deferred = bpf_kprobe_multi_link_dealloc,
.fill_link_info = bpf_kprobe_multi_link_fill_link_info,
+#ifdef CONFIG_PROC_FS
+ .show_fdinfo = bpf_kprobe_multi_show_fdinfo,
+#endif
};
static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
--
2.48.1
