Re: [PATCH v1 0/3] x86/cpufeatures: Automatically generate required and disabled feature masks

[Xin Li]

On 1/31/2024 9:46 PM, Xin Li (Intel) wrote:
> When a CPU feature is not configured, e.g., CONFIG_X86_FRED=n, in a
> build config, its feature disable flag, e.g. DISABLE_FRED, needs to
> be defined and added to a specific disabled CPU features mask in
> <asm/disabled-features.h>, as the following commit:
> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=x86/fred&id=e554a8ca49d6d6d782f546ae4d7f036946e7dd87
>
> This patch set adds an awk script to automatically generate a header
> with required and disabled CPU features masks based on build config.

A gentle ping.

This is an infrastructural improvement which has a lower priority,
however it would be nice to get some feedback first.

Thanks!
    Xin


> H. Peter Anvin (Intel) (2):
>    x86/cpufeatures: Add {required,disabled} feature configs
>    x86/cpufeatures: Generate a feature mask header based on build config
>
> Xin Li (Intel) (1):
>    x86/cpufeatures: Remove {disabled,required}-features.h
>
>   arch/x86/Kconfig                              |   4 +-
>   arch/x86/Kconfig.cpu                          |  16 +-
>   arch/x86/Kconfig.cpufeatures                  | 149 +++++++++++++++++
>   arch/x86/Makefile                             |  17 +-
>   arch/x86/boot/cpucheck.c                      |   3 +-
>   arch/x86/boot/cpuflags.c                      |   1 -
>   arch/x86/boot/mkcpustr.c                      |   3 +-
>   arch/x86/include/asm/Kbuild                   |   1 +
>   arch/x86/include/asm/asm-prototypes.h         |   2 +-
>   arch/x86/include/asm/atomic64_32.h            |   2 +-
>   arch/x86/include/asm/bitops.h                 |   4 +-
>   arch/x86/include/asm/cmpxchg_32.h             |   4 +-
>   arch/x86/include/asm/cpufeature.h             |   1 +
>   arch/x86/include/asm/cpufeatures.h            |   8 -
>   arch/x86/include/asm/disabled-features.h      | 154 ------------------
>   arch/x86/include/asm/required-features.h      | 104 ------------
>   arch/x86/kernel/verify_cpu.S                  |   1 +
>   arch/x86/lib/Makefile                         |   2 +-
>   arch/x86/lib/cmpxchg8b_emu.S                  |   2 +-
>   arch/x86/tools/featuremasks.awk               | 108 ++++++++++++
>   lib/atomic64_test.c                           |   2 +-
>   tools/arch/x86/include/asm/cpufeatures.h      |   8 -
>   .../arch/x86/include/asm/disabled-features.h  | 154 ------------------
>   .../arch/x86/include/asm/required-features.h  | 104 ------------
>   tools/perf/check-headers.sh                   |   2 -
>   25 files changed, 303 insertions(+), 553 deletions(-)
>   create mode 100644 arch/x86/Kconfig.cpufeatures
>   delete mode 100644 arch/x86/include/asm/disabled-features.h
>   delete mode 100644 arch/x86/include/asm/required-features.h
>   create mode 100755 arch/x86/tools/featuremasks.awk
>   delete mode 100644 tools/arch/x86/include/asm/disabled-features.h
>   delete mode 100644 tools/arch/x86/include/asm/required-features.h
>
>
> base-commit: 078b7b997b47c7166c1240cf1d39db9f646a56be

--
Thanks!
    Xin