On Mon, Jul 1, 2024 at 9:42 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Adding support to attach program in uprobe session mode
> with bpf_program__attach_uprobe_multi function.
>
> Adding session bool to bpf_uprobe_multi_opts struct that allows
> to load and attach the bpf program via uprobe session.
> the attachment to create uprobe multi session.
>
> Also adding new program loader section that allows:
> SEC("uprobe.session/bpf_fentry_test*")
>
> and loads/attaches uprobe program as uprobe session.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
> tools/lib/bpf/bpf.c | 1 +
> tools/lib/bpf/libbpf.c | 50 ++++++++++++++++++++++++++++++++++++++++--
> tools/lib/bpf/libbpf.h | 4 +++-
> 3 files changed, 52 insertions(+), 3 deletions(-)
>
[...]
> @@ -9362,6 +9363,7 @@ static const struct bpf_sec_def section_defs[] = {
> SEC_DEF("kprobe.session+", KPROBE, BPF_TRACE_KPROBE_SESSION, SEC_NONE, attach_kprobe_session),
> SEC_DEF("uprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi),
> SEC_DEF("uretprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi),
> + SEC_DEF("uprobe.session+", KPROBE, BPF_TRACE_UPROBE_SESSION, SEC_NONE, attach_uprobe_session),
sleepable ones as well?
> SEC_DEF("uprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi),
> SEC_DEF("uretprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi),
> SEC_DEF("ksyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall),
> @@ -11698,6 +11700,40 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru
> return ret;
> }
>
> +static int attach_uprobe_session(const struct bpf_program *prog, long cookie, struct bpf_link **link)
> +{
> + char *binary_path = NULL, *func_name = NULL;
> + LIBBPF_OPTS(bpf_uprobe_multi_opts, opts,
> + .session = true,
> + );
nit: keep a single line?
> + int n, ret = -EINVAL;
> + const char *spec;
> +
> + *link = NULL;
> +
> + spec = prog->sec_name + sizeof("uprobe.session/") - 1;
> + n = sscanf(spec, "%m[^:]:%m[^\n]",
> + &binary_path, &func_name);
single line, wrapping lines is a necessary evil, please
[...]
