Commit 5bfdd32d authored by Jiri Olsa's avatar Jiri Olsa Committed by Alexei Starovoitov
Browse files

libbpf: Add support for u[ret]probe.multi[.s] program sections 



Adding support for several uprobe_multi program sections
to allow auto attach of multi_uprobe programs.

Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230809083440.3209381-16-jolsa@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 3140cf12

tools/lib/bpf/libbpf.c

+36 −0
Original line number Original line Diff line number Diff line
@@ -8701,6 +8701,7 @@ static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_lin 
static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link);

static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link);

static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_link **link);

static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_link **link);

static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link);

static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link);

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_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_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link);
@@ -8716,6 +8717,10 @@ static const struct bpf_sec_def section_defs[] = { 
	SEC_DEF("uretprobe.s+",		KPROBE, 0, SEC_SLEEPABLE, attach_uprobe),

	SEC_DEF("uretprobe.s+",		KPROBE, 0, SEC_SLEEPABLE, attach_uprobe),

	SEC_DEF("kprobe.multi+",	KPROBE,	BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),

	SEC_DEF("kprobe.multi+",	KPROBE,	BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),

	SEC_DEF("kretprobe.multi+",	KPROBE,	BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),

	SEC_DEF("kretprobe.multi+",	KPROBE,	BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),

	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.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),

	SEC_DEF("ksyscall+",		KPROBE,	0, SEC_NONE, attach_ksyscall),

	SEC_DEF("kretsyscall+",		KPROBE, 0, SEC_NONE, attach_ksyscall),

	SEC_DEF("kretsyscall+",		KPROBE, 0, SEC_NONE, attach_ksyscall),

	SEC_DEF("usdt+",		KPROBE,	0, SEC_NONE, attach_usdt),

	SEC_DEF("usdt+",		KPROBE,	0, SEC_NONE, attach_usdt),
@@ -10922,6 +10927,37 @@ static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, stru 
	return libbpf_get_error(*link);

	return libbpf_get_error(*link);

}

}





static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link)

{

	char *probe_type = NULL, *binary_path = NULL, *func_name = NULL;

	LIBBPF_OPTS(bpf_uprobe_multi_opts, opts);

	int n, ret = -EINVAL;



	*link = NULL;



	n = sscanf(prog->sec_name, "%m[^/]/%m[^:]:%ms",

		   &probe_type, &binary_path, &func_name);

	switch (n) {

	case 1:

		/* handle SEC("u[ret]probe") - format is valid, but auto-attach is impossible. */

		ret = 0;

		break;

	case 3:

		opts.retprobe = strcmp(probe_type, "uretprobe.multi") == 0;

		*link = bpf_program__attach_uprobe_multi(prog, -1, binary_path, func_name, &opts);

		ret = libbpf_get_error(*link);

		break;

	default:

		pr_warn("prog '%s': invalid format of section definition '%s'\n", prog->name,

			prog->sec_name);

		break;

	}

	free(probe_type);

	free(binary_path);

	free(func_name);

	return ret;

}



static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz,

static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz,

					 const char *binary_path, uint64_t offset)

					 const char *binary_path, uint64_t offset)

{

{