libbpf: Migrate internal use of bpf_program__get_prog_info_linear

In preparation for bpf_program__get_prog_info_linear deprecation, move
the single use in libbpf to call bpf_obj_get_info_by_fd directly.

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211011082031.4148337-2-davemarchevsky@fb.com

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 63d7386..760c7e3 100644 (file)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -8461,28 +8461,27 @@ int libbpf_find_vmlinux_btf_id(const char *name,
 
 static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd)
 {
-       struct bpf_prog_info_linear *info_linear;
-       struct bpf_prog_info *info;
+       struct bpf_prog_info info = {};
+       __u32 info_len = sizeof(info);
        struct btf *btf;
        int err;
 
-       info_linear = bpf_program__get_prog_info_linear(attach_prog_fd, 0);
-       err = libbpf_get_error(info_linear);
+       err = bpf_obj_get_info_by_fd(attach_prog_fd, &info, &info_len);
        if (err) {
-               pr_warn("failed get_prog_info_linear for FD %d\n",
-                       attach_prog_fd);
+               pr_warn("failed bpf_obj_get_info_by_fd for FD %d: %d\n",
+                       attach_prog_fd, err);
                return err;
        }
 
        err = -EINVAL;
-       info = &info_linear->info;
-       if (!info->btf_id) {
+       if (!info.btf_id) {
                pr_warn("The target program doesn't have BTF\n");
                goto out;
        }
-       btf = btf__load_from_kernel_by_id(info->btf_id);
-       if (libbpf_get_error(btf)) {
-               pr_warn("Failed to get BTF of the program\n");
+       btf = btf__load_from_kernel_by_id(info.btf_id);
+       err = libbpf_get_error(btf);
+       if (err) {
+               pr_warn("Failed to get BTF %d of the program: %d\n", info.btf_id, err);
                goto out;
        }
        err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC);
@@ -8492,7 +8491,6 @@ static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd)
                goto out;
        }
 out:
-       free(info_linear);
        return err;
 }