[PATCHv8 bpf-next 16/29] bpf: Add support for tracing_multi link fdinfo
From: Jiri Olsa <jolsa@kernel.org>
Date: 2026-06-06 12:42:42
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [security & lsm] (security audit and enforcement using bpf), bpf [tracing], the rest, tracing · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, KP Singh, Matt Bobrowski, Song Liu, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Adding tracing_multi link fdinfo support with following output: pos: 0 flags: 02000000 mnt_id: 19 ino: 3087 link_type: tracing_multi link_id: 9 prog_tag: 599ba0e317244f86 prog_id: 94 attach_type: 59 cnt: 10 obj-id btf-id cookie func 1 91593 8 bpf_fentry_test1+0x4/0x10 1 91595 9 bpf_fentry_test2+0x4/0x10 1 91596 7 bpf_fentry_test3+0x4/0x20 1 91597 5 bpf_fentry_test4+0x4/0x20 1 91598 4 bpf_fentry_test5+0x4/0x20 1 91599 2 bpf_fentry_test6+0x4/0x20 1 91600 3 bpf_fentry_test7+0x4/0x10 1 91601 1 bpf_fentry_test8+0x4/0x10 1 91602 10 bpf_fentry_test9+0x4/0x10 1 91594 6 bpf_fentry_test10+0x4/0x10 Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- kernel/trace/bpf_trace.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index a0d688fffc5a..90432f0fc2a8 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c@@ -3665,9 +3665,39 @@ static void bpf_tracing_multi_link_dealloc(struct bpf_link *link) kvfree(tr_link); } +#ifdef CONFIG_PROC_FS +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; + + 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"); + for (int i = 0; i < tr_link->nodes_cnt; i++) { + struct bpf_tracing_multi_node *mnode = &tr_link->nodes[i]; + 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); + + cond_resched(); + } +} +#endif + static const struct bpf_link_ops bpf_tracing_multi_link_lops = { .release = bpf_tracing_multi_link_release, .dealloc_deferred = bpf_tracing_multi_link_dealloc, +#ifdef CONFIG_PROC_FS + .show_fdinfo = bpf_tracing_multi_show_fdinfo, +#endif }; static int ids_cmp_r(const void *pa, const void *pb, const void *priv __maybe_unused)
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2.54.0