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: Stanislav Fomichev <sdf@google.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Message-ID: <20240319233852.1977493-5-andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Andrii Nakryiko 2024-03-19 16:38:51 -07:00 committed by Alexei Starovoitov
parent 68ca5d4eeb
commit 36ffb2023e
5 changed files with 53 additions and 5 deletions

View file

@ -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);

View file

@ -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,

View file

@ -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[] = {

View file

@ -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 */

View file

@ -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;