On Tue, Feb 3, 2026 at 1:40 AM Jiri Olsa <[email protected]> wrote:
>
> Adding new interface function to attach programs with tracing
> multi link:
>
> bpf_program__attach_tracing_multi(const struct bpf_program *prog,
> const char *pattern,
> const struct bpf_tracing_multi_opts
> *opts);
>
> The program is attach to functions specified by pattern or by
> btf IDs specified in bpf_tracing_multi_opts object.
>
> Adding support for new sections to attach programs with above
> functions:
>
> fentry.multi/pattern
> fexit.multi/pattern
>
> Signed-off-by: Jiri Olsa <[email protected]>
> ---
> tools/lib/bpf/bpf.c | 7 ++++
> tools/lib/bpf/bpf.h | 4 ++
> tools/lib/bpf/libbpf.c | 87 ++++++++++++++++++++++++++++++++++++++++
> tools/lib/bpf/libbpf.h | 14 +++++++
> tools/lib/bpf/libbpf.map | 1 +
> 5 files changed, 113 insertions(+)
[...]
> static const char * const map_type_name[] = {
> @@ -9814,6 +9817,7 @@ static int attach_kprobe_session(const struct
> bpf_program *prog, long cookie, st
> static int attach_uprobe_multi(const struct bpf_program *prog, long cookie,
> struct bpf_link **link);
> static int attach_lsm(const struct bpf_program *prog, long cookie, struct
> bpf_link **link);
> static int attach_iter(const struct bpf_program *prog, long cookie, struct
> bpf_link **link);
> +static int attach_tracing_multi(const struct bpf_program *prog, long cookie,
> struct bpf_link **link);
>
> static const struct bpf_sec_def section_defs[] = {
> SEC_DEF("socket", SOCKET_FILTER, 0, SEC_NONE),
> @@ -9862,6 +9866,8 @@ static const struct bpf_sec_def section_defs[] = {
> SEC_DEF("fexit.s+", TRACING, BPF_TRACE_FEXIT,
> SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
> SEC_DEF("fsession+", TRACING, BPF_TRACE_FSESSION,
> SEC_ATTACH_BTF, attach_trace),
> SEC_DEF("fsession.s+", TRACING, BPF_TRACE_FSESSION,
> SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
> + SEC_DEF("fentry.multi+", TRACING, BPF_TRACE_FENTRY_MULTI, 0,
> attach_tracing_multi),
> + SEC_DEF("fexit.multi+", TRACING, BPF_TRACE_FEXIT_MULTI, 0,
> attach_tracing_multi),
> SEC_DEF("freplace+", EXT, 0, SEC_ATTACH_BTF, attach_trace),
> SEC_DEF("lsm+", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF,
> attach_lsm),
> SEC_DEF("lsm.s+", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF |
> SEC_SLEEPABLE, attach_lsm),
> @@ -12237,6 +12243,87 @@ static int attach_uprobe_multi(const struct
> bpf_program *prog, long cookie, stru
> return ret;
> }
>
> +struct bpf_link *
> +bpf_program__attach_tracing_multi(const struct bpf_program *prog, const char
> *pattern,
> + const struct bpf_tracing_multi_opts *opts)
> +{
> + LIBBPF_OPTS(bpf_link_create_opts, lopts);
> + __u32 *btf_ids, cnt, *free_ids = NULL;
> + int prog_fd, link_fd, err;
> + struct bpf_link *link;
> +
> + btf_ids = OPTS_GET(opts, btf_ids, false);
> + cnt = OPTS_GET(opts, cnt, false);
> +
> + if (!pattern && !btf_ids && !cnt)
let's check that either both btf_ids and cnt are specified or none
then we can check that either pattern or btf_ids are specified
still two checks, but will capture all the bad cases
> + return libbpf_err_ptr(-EINVAL);
> + if (pattern && (btf_ids || cnt))
> + return libbpf_err_ptr(-EINVAL);
> +
[...]
> struct bpf_uprobe_opts {
> /* size of this struct, for forward/backward compatibility */
> size_t sz;
> diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
> index d18fbcea7578..a3ffb21270e9 100644
> --- a/tools/lib/bpf/libbpf.map
> +++ b/tools/lib/bpf/libbpf.map
> @@ -358,6 +358,7 @@ LIBBPF_1.0.0 {
> bpf_program__attach_ksyscall;
> bpf_program__autoattach;
> bpf_program__set_autoattach;
> + bpf_program__attach_tracing_multi;
stuck in the past? ;) we are in 1.7 cycle
> btf__add_enum64;
> btf__add_enum64_value;
> libbpf_bpf_attach_type_str;
> --
> 2.52.0
>
