On Tue, Jul 29, 2025 at 11:33:35AM -0400, Steven Rostedt wrote:
SNIP
> +/**
> + * btf_find_offset - Find an offset of a member for a structure
> + * @arg: A structure name followed by one or more members
> + * @offset_p: A pointer to where to store the offset
> + *
> + * Will parse @arg with the expected format of: struct.member[[.member]..]
> + * It is delimited by '.'. The first item must be a structure type.
> + * The next are its members. If the member is also of a structure type it
> + * another member may follow ".member".
> + *
> + * Note, @arg is modified but will be put back to what it was on return.
> + *
> + * Returns: 0 on success and -EINVAL if no '.' is present
> + * or -ENXIO if the structure or member is not found.
> + * Returns -EINVAL if BTF is not defined.
> + * On success, @offset_p will contain the offset of the member specified
> + * by @arg.
> + */
> +int btf_find_offset(char *arg, long *offset_p)
> +{
> + const struct btf_type *t;
> + struct btf *btf;
> + long offset = 0;
> + char *ptr;
> + int ret;
> + s32 id;
> +
> + ptr = strchr(arg, '.');
> + if (!ptr)
> + return -EINVAL;
> +
> + *ptr = '\0';
> +
> + id = bpf_find_btf_id(arg, BTF_KIND_STRUCT, &btf);
hi,
I think you need to call btf_put(btf) before return
jirka
> + if (id < 0)
> + goto error;
> +
> + /* Get BTF_KIND_FUNC type */
> + t = btf_type_by_id(btf, id);
> +
> + /* May allow more than one member, as long as they are structures */
> + do {
> + if (!t || !btf_type_is_struct(t))
> + goto error;
> +
> + *ptr++ = '.';
> + arg = ptr;
> + ptr = strchr(ptr, '.');
> + if (ptr)
> + *ptr = '\0';
> +
> + ret = find_member(arg, btf, &t, 0);
> + if (ret < 0)
> + goto error;
> +
> + offset += ret;
> +
> + } while (ptr);
> +
> + *offset_p = offset;
> + return 0;
> +
> +error:
> + if (ptr)
> + *ptr = '.';
> + return -ENXIO;
> +}
SNIP
