Commit 36ffb202 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
Browse files

libbpf: add support for BPF cookie for raw_tp/tp_btf programs 



Wire up BPF cookie passing or raw_tp and tp_btf programs, both in
low-level and high-level APIs.

Acked-by: default avatarStanislav Fomichev <sdf@google.com>
Acked-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Message-ID: <20240319233852.1977493-5-andrii@kernel.org>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 68ca5d4e

tools/lib/bpf/bpf.c

+14 −2
Original line number Diff line number Diff line
@@ -785,6 +785,7 @@ int bpf_link_create(int prog_fd, int target_fd, 
		if (!OPTS_ZEROED(opts, uprobe_multi))

			return libbpf_err(-EINVAL);

		break;

	case BPF_TRACE_RAW_TP:

	case BPF_TRACE_FENTRY:

	case BPF_TRACE_FEXIT:

	case BPF_MODIFY_RETURN:
@@ -1173,20 +1174,31 @@ int bpf_link_get_info_by_fd(int link_fd, struct bpf_link_info *info, __u32 *info 
	return bpf_obj_get_info_by_fd(link_fd, info, info_len);

}



int bpf_raw_tracepoint_open(const char *name, int prog_fd)

int bpf_raw_tracepoint_open_opts(int prog_fd, struct bpf_raw_tp_opts *opts)

{

	const size_t attr_sz = offsetofend(union bpf_attr, raw_tracepoint);

	union bpf_attr attr;

	int fd;



	if (!OPTS_VALID(opts, bpf_raw_tp_opts))

		return libbpf_err(-EINVAL);



	memset(&attr, 0, attr_sz);

	attr.raw_tracepoint.name = ptr_to_u64(name);

	attr.raw_tracepoint.prog_fd = prog_fd;

	attr.raw_tracepoint.name = ptr_to_u64(OPTS_GET(opts, tp_name, NULL));

	attr.raw_tracepoint.cookie = OPTS_GET(opts, cookie, 0);



	fd = sys_bpf_fd(BPF_RAW_TRACEPOINT_OPEN, &attr, attr_sz);

	return libbpf_err_errno(fd);

}



int bpf_raw_tracepoint_open(const char *name, int prog_fd)

{

	LIBBPF_OPTS(bpf_raw_tp_opts, opts, .tp_name = name);



	return bpf_raw_tracepoint_open_opts(prog_fd, &opts);

}



int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts)

{

	const size_t attr_sz = offsetofend(union bpf_attr, btf_token_fd);

tools/lib/bpf/bpf.h

+9 −0
Original line number Diff line number Diff line
@@ -617,6 +617,15 @@ LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type, 
			      __u32 query_flags, __u32 *attach_flags,

			      __u32 *prog_ids, __u32 *prog_cnt);



struct bpf_raw_tp_opts {

	size_t sz; /* size of this struct for forward/backward compatibility */

	const char *tp_name;

	__u64 cookie;

	size_t :0;

};

#define bpf_raw_tp_opts__last_field cookie



LIBBPF_API int bpf_raw_tracepoint_open_opts(int prog_fd, struct bpf_raw_tp_opts *opts);

LIBBPF_API int bpf_raw_tracepoint_open(const char *name, int prog_fd);

LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf,

				 __u32 *buf_len, __u32 *prog_id, __u32 *fd_type,

tools/lib/bpf/libbpf.c

+17 −3
Original line number Diff line number Diff line
@@ -12309,13 +12309,19 @@ static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_lin 
	return libbpf_get_error(*link);

}



struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,

						    const char *tp_name)

struct bpf_link *

bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog,

					const char *tp_name,

					struct bpf_raw_tracepoint_opts *opts)

{

	LIBBPF_OPTS(bpf_raw_tp_opts, raw_opts);

	char errmsg[STRERR_BUFSIZE];

	struct bpf_link *link;

	int prog_fd, pfd;



	if (!OPTS_VALID(opts, bpf_raw_tracepoint_opts))

		return libbpf_err_ptr(-EINVAL);



	prog_fd = bpf_program__fd(prog);

	if (prog_fd < 0) {

		pr_warn("prog '%s': can't attach before loaded\n", prog->name);
@@ -12327,7 +12333,9 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *pr 
		return libbpf_err_ptr(-ENOMEM);

	link->detach = &bpf_link__detach_fd;



	pfd = bpf_raw_tracepoint_open(tp_name, prog_fd);

	raw_opts.tp_name = tp_name;

	raw_opts.cookie = OPTS_GET(opts, cookie, 0);

	pfd = bpf_raw_tracepoint_open_opts(prog_fd, &raw_opts);

	if (pfd < 0) {

		pfd = -errno;

		free(link);
@@ -12339,6 +12347,12 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *pr 
	return link;

}



struct bpf_link *bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,

						    const char *tp_name)

{

	return bpf_program__attach_raw_tracepoint_opts(prog, tp_name, NULL);

}



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

{

	static const char *const prefixes[] = {

tools/lib/bpf/libbpf.h

+11 −0
Original line number Diff line number Diff line
@@ -760,9 +760,20 @@ bpf_program__attach_tracepoint_opts(const struct bpf_program *prog, 
				    const char *tp_name,

				    const struct bpf_tracepoint_opts *opts);



struct bpf_raw_tracepoint_opts {

	size_t sz; /* size of this struct for forward/backward compatibility */

	__u64 cookie;

	size_t :0;

};

#define bpf_raw_tracepoint_opts__last_field cookie



LIBBPF_API struct bpf_link *

bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,

				   const char *tp_name);

LIBBPF_API struct bpf_link *

bpf_program__attach_raw_tracepoint_opts(const struct bpf_program *prog,

					const char *tp_name,

					struct bpf_raw_tracepoint_opts *opts);



struct bpf_trace_opts {

	/* size of this struct, for forward/backward compatibility */

tools/lib/bpf/libbpf.map

+2 −0
Original line number Diff line number Diff line
@@ -410,6 +410,8 @@ LIBBPF_1.3.0 { 


LIBBPF_1.4.0 {

	global:

		bpf_program__attach_raw_tracepoint_opts;

		bpf_raw_tracepoint_open_opts;

		bpf_token_create;

		btf__new_split;

		btf_ext__raw_data;