[PATCH v3 0/5] linux/const.h: cleanups of macros such as UL(), _BITUL(), BIT() etc.
From: Masahiro Yamada <hidden>
Date: 2018-02-22 12:17:31
Also in:
lkml
ARM, ARM64, UniCore32 define UL() as a shorthand of _AC(..., UL). More architectures may introduce it in the future. UL() is arch-agnostic, and useful. So let's move it to include/linux/const.h Currently, <asm/memory.h> must be included to use UL(). It pulls in more bloats just for defining some bit macros. I posted V2 one year ago. The previous posts are: https://patchwork.kernel.org/patch/9498273/ https://patchwork.kernel.org/patch/9498275/ https://patchwork.kernel.org/patch/9498269/ https://patchwork.kernel.org/patch/9498271/ At that time, what blocked this series was a comment from David Howells: You need to be very careful doing this. Some userspace stuff depends on the guard macro names on the kernel header files. (https://patchwork.kernel.org/patch/9498275/) Looking at the code closer, I noticed this is not a problem. See the following line. https://github.com/torvalds/linux/blob/v4.16-rc2/scripts/headers_install.sh#L40 scripts/headers_install.sh rips off _UAPI prefix from guard macro names. I ran "make headers_install" and confirmed the result is what I expect. So, we can prefix the include guard of include/uapi/linux/const.h, and add a new include/linux/const.h. Masahiro Yamada (5): linux/const.h: prefix include guard of uapi/linux/const.h with _UAPI m68k: rename UL() to TO_UL() linux/const.h: move UL() macro to include/linux/const.h linux/const.h: refactor _BITUL and _BITULL a bit linux/const.h: move BIT(_ULL) to linux/const.h for use in assembly arch/arm/include/asm/memory.h | 6 ------ arch/arm64/include/asm/memory.h | 6 ------ arch/m68k/mm/init.c | 6 +++--- arch/unicore32/include/asm/memory.h | 6 ------ include/linux/bitops.h | 3 +-- include/linux/const.h | 12 ++++++++++++ include/uapi/linux/const.h | 13 ++++++++----- 7 files changed, 24 insertions(+), 28 deletions(-) create mode 100644 include/linux/const.h -- 2.7.4