Re: [PATCH v2 0/8] centralize AVX-512 feature detection

[David Marchand <david.marchand@redhat.com>]

On Tue, Oct 1, 2024 at 1:19 PM Bruce Richardson
<bruce.richardson@intel.com> wrote:
>
> The meson code to detect CPU and compiler support for AVX512 was duplicated
> across multiple drivers. Do all detection in just a single place to simplify
> the code.
>
> v2: ensure that target_has_avx512 is always defined on x86 to fix build errors
>
> Bruce Richardson (8):
>   config/x86: add global defines for checking AVX-512
>   event/dlb2: use global AVX-512 variables
>   common/idpf: use global AVX-512 variables
>   net/cpfl: use global AVX-512 variables
>   net/i40e: use global AVX-512 variables
>   net/iavf: use global AVX-512 variables
>   net/ice: use global AVX-512 variables
>   net/idpf: use global AVX-512 variables
>
>  config/x86/meson.build          | 19 +++++++++++----
>  drivers/common/idpf/meson.build | 17 ++-----------
>  drivers/event/dlb2/meson.build  | 42 +++++++--------------------------
>  drivers/net/cpfl/meson.build    | 19 ++-------------
>  drivers/net/i40e/meson.build    | 13 ++--------
>  drivers/net/iavf/meson.build    | 13 ++--------
>  drivers/net/ice/meson.build     | 15 ++----------
>  drivers/net/idpf/meson.build    | 19 ++-------------
>  8 files changed, 36 insertions(+), 121 deletions(-)

Thanks for this cleanup, I have two comments.

- Some drivers were going into great lenghts to check that individiual
avx512 features were available.
With this series, we end up requiring support for all features to
announce avx512 availability.
Are we perhaps disabling AVX512 support with some toolchains, out
there, supporting only part of the set?

- Some drivers were checking for presence of -mno-avx512f in
machine_args as a way to disable building any AVX512 stuff.
This gets discarded with this series.


-- 
David Marchand