Re: [PATCH 1/2] x86/efi: Optimize away setup_gop32/64 if unused

Matt Fleming
2016-09-05T12:37:31Z

On Mon, 22 Aug, at 12:01:21PM, Lukas Wunner wrote:
> Eliminate the 64 bit code path when compiling for x86_32, and vice-versa
> the 32 bit code path when compiling for x86_64 with mixed mode disabled.
>
> Size of gop.o text section:
> CONFIG_X86_32: 1758 before, 1299 after
> CONFIG_X86_64 && !CONFIG_EFI_MIXED: 2201 before, 1406 after
> CONFIG_X86_64 && CONFIG_EFI_MIXED: 2201 before and after
>
> Signed-off-by: Lukas Wunner <lukas@wunner.de>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
> arch/x86/include/asm/efi.h | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
> index 6b06939..1bda245 100644
> --- a/arch/x86/include/asm/efi.h
> +++ b/arch/x86/include/asm/efi.h
> @@ -207,14 +207,16 @@ struct efi_config {
>
> __pure const struct efi_config *__efi_early(void);
>
> +#define efi_is_64bit() \
> + (IS_ENABLED(CONFIG_X86_64) && (!IS_ENABLED(CONFIG_EFI_MIXED) \
> + || __efi_early()->is64))
> +
> #define efi_call_early(f, ...) \
> __efi_early()->call(__efi_early()->f, __VA_ARGS__);
>
> #define __efi_call_early(f, ...) \
> __efi_early()->call((unsigned long)f, __VA_ARGS__);
>
> -#define efi_is_64bit() __efi_early()->is64
> -
> extern bool efi_reboot_required(void);
>
> #else

Could you make this into a more readable static inline? e.g. something
like this,

static inline bool efi_is_64bit(void)
{
if (!IS_ENABLED(CONFIG_X86_64))
return false;

if (!IS_ENABLED(CONFIG_EFI_MIXED) || __efi_early()->is64)
return true;

return false;
}