On Mon, Sep 13, 2021 at 8:51 AM Yonghong Song <yhs@xxxxxx> wrote:
>
> Change BTF_KIND_* macros to enums so they are encoded in dwarf and
> appear in vmlinux.h. This will make it easier for bpf programs
> to use these constants without macro definitions.
>
> Signed-off-by: Yonghong Song <yhs@xxxxxx>
> ---
> include/uapi/linux/btf.h | 36 ++++++++++++++++++----------------
> tools/include/uapi/linux/btf.h | 36 ++++++++++++++++++----------------
> 2 files changed, 38 insertions(+), 34 deletions(-)
>
> diff --git a/include/uapi/linux/btf.h b/include/uapi/linux/btf.h
> index d27b1708efe9..c32cd6697d63 100644
> --- a/include/uapi/linux/btf.h
> +++ b/include/uapi/linux/btf.h
> @@ -56,23 +56,25 @@ struct btf_type {
> #define BTF_INFO_VLEN(info) ((info) & 0xffff)
> #define BTF_INFO_KFLAG(info) ((info) >> 31)
>
> -#define BTF_KIND_UNKN 0 /* Unknown */
> -#define BTF_KIND_INT 1 /* Integer */
> -#define BTF_KIND_PTR 2 /* Pointer */
> -#define BTF_KIND_ARRAY 3 /* Array */
> -#define BTF_KIND_STRUCT 4 /* Struct */
> -#define BTF_KIND_UNION 5 /* Union */
> -#define BTF_KIND_ENUM 6 /* Enumeration */
> -#define BTF_KIND_FWD 7 /* Forward */
> -#define BTF_KIND_TYPEDEF 8 /* Typedef */
> -#define BTF_KIND_VOLATILE 9 /* Volatile */
> -#define BTF_KIND_CONST 10 /* Const */
> -#define BTF_KIND_RESTRICT 11 /* Restrict */
> -#define BTF_KIND_FUNC 12 /* Function */
> -#define BTF_KIND_FUNC_PROTO 13 /* Function Proto */
> -#define BTF_KIND_VAR 14 /* Variable */
> -#define BTF_KIND_DATASEC 15 /* Section */
> -#define BTF_KIND_FLOAT 16 /* Floating point */
> +enum {
> + BTF_KIND_UNKN = 0, /* Unknown */
> + BTF_KIND_INT, /* Integer */
> + BTF_KIND_PTR, /* Pointer */
> + BTF_KIND_ARRAY, /* Array */
> + BTF_KIND_STRUCT, /* Struct */
> + BTF_KIND_UNION, /* Union */
> + BTF_KIND_ENUM, /* Enumeration */
> + BTF_KIND_FWD, /* Forward */
> + BTF_KIND_TYPEDEF, /* Typedef */
> + BTF_KIND_VOLATILE, /* Volatile */
> + BTF_KIND_CONST, /* Const */
> + BTF_KIND_RESTRICT, /* Restrict */
> + BTF_KIND_FUNC, /* Function */
> + BTF_KIND_FUNC_PROTO, /* Function Proto */
> + BTF_KIND_VAR, /* Variable */
> + BTF_KIND_DATASEC, /* Section */
> + BTF_KIND_FLOAT, /* Floating point */
Can you please leave explicit integer values specified? It's extremely
helpful and much easier in practice, compared to having to count the
number of rows from BTF_KIND_UNKN. Had to do it multiple times with
other BPF constants and was happy I didn't have to do that for
BTF_KIND enums.
> +};
> #define BTF_KIND_MAX BTF_KIND_FLOAT
> #define NR_BTF_KINDS (BTF_KIND_MAX + 1)
these two can be just an enum values as well, and actually will be
"auto-updated", if done this way (I think, haven't really tested)
BTF_KIND_FLOAT = 16,
NR_BTF_KINDS,
BTF_KIND_MAX = NR_BTF_KINDS - 1,
... won't it?
[...]
