lkml.org 
[lkml]   [2018]   [Mar]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v3 5/5] linux/const.h: move BIT(_ULL) to linux/const.h for use in assembly
Hi Andrew,

2018-02-22 21:15 GMT+09:00 Masahiro Yamada <yamada.masahiro@socionext.com>:
> Commit 2fc016c5bd8a ("linux/const.h: Add _BITUL() and _BITULL()")
> introduced _BITUL() and _BITULL(). Its git-log says the difference
> from the already existing BIT() are:
>
> 1. The namespace is such that they can be used in uapi definitions.
> 2. The type is set with the _AC() macro to allow it to be used in
> assembly.
> 3. The type is explicitly specified to be UL or ULL.
>
> However, I found _BITUL() is mostly used in kernel-space since it is
> handy to share headers between C and assembly. If we only need '2.',
> we can improve the existing BIT() for use in assembly, allowing us to
> avoid unnecessary underscore prefixes.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---

This patch conflicts with the one from Will Deacon.
(https://patchwork.kernel.org/patch/10242531/)

I think his patch is better than mine.

So, could you drop this one from your tree, please?
(only this one from the series.)

Thanks




> V2: https://patchwork.kernel.org/patch/9498271/
>
> Changes in v3: None
> Changes in v2: None
>
> include/linux/bitops.h | 3 +--
> include/linux/const.h | 3 +++
> 2 files changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index 4cac4e1..8a856be 100644
> --- a/include/linux/bitops.h
> +++ b/include/linux/bitops.h
> @@ -1,11 +1,10 @@
> /* SPDX-License-Identifier: GPL-2.0 */
> #ifndef _LINUX_BITOPS_H
> #define _LINUX_BITOPS_H
> +#include <linux/const.h>
> #include <asm/types.h>
>
> #ifdef __KERNEL__
> -#define BIT(nr) (1UL << (nr))
> -#define BIT_ULL(nr) (1ULL << (nr))
> #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
> #define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
> #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
> diff --git a/include/linux/const.h b/include/linux/const.h
> index 7b55a55..200892d 100644
> --- a/include/linux/const.h
> +++ b/include/linux/const.h
> @@ -6,4 +6,7 @@
> #define UL(x) (_UL(x))
> #define ULL(x) (_ULL(x))
>
> +#define BIT(x) (_BITUL(x))
> +#define BIT_ULL(x) (_BITULL(x))
> +
> #endif /* _LINUX_CONST_H */
> --
> 2.7.4
>



--
Best Regards
Masahiro Yamada

\
 
 \ /
  Last update: 2018-03-13 09:42    [W:0.119 / U:4.732 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site