Re: [RFC PATCH] drivers: add generic build of SVE files

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

On Mon, Apr 7, 2025 at 5:29 PM Bruce Richardson
<bruce.richardson@intel.com> wrote:
>
> For SVE, as for AVX2 and AVX-512, support building files for these ISAs
> from the top-level drivers/meson.build file, rather than having each
> driver re-implement it.
>
> This removes the remaining build task for drivers in DPDK which is
> being done by a driver itself, rather than in the generic drivers'
> build rules.
>
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Thanks for working on this additional cleanup.


> ---
>  drivers/meson.build          | 27 +++++++++++++++++++++++++++
>  drivers/net/hns3/meson.build | 22 +---------------------
>  2 files changed, 28 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/meson.build b/drivers/meson.build
> index b2d2537dc8..a6f0670a2f 100644
> --- a/drivers/meson.build
> +++ b/drivers/meson.build
> @@ -128,6 +128,7 @@ foreach subpath:subdirs
>          sources = []
>          sources_avx2 = []
>          sources_avx512 = []
> +        sources_sve = []
>          headers = []
>          driver_sdk_headers = [] # public headers included by drivers
>          objs = []
> @@ -285,6 +286,32 @@ foreach subpath:subdirs
>              endif
>          endif
>
> +        if (arch_subdir == 'arm' and sources_sve.length() > 0
> +                and cc.has_argument('-march=armv8.2-a+sve')
> +                and cc.check_header('arm_sve.h'))
> +
> +            if dpdk_conf.has('RTE_HAS_SVE_ACLE')
> +                sources += sources_sve

Do we need this special case?


> +            else
> +                cflags += ['-DRTE_HAS_SVE_ACLE=1']
> +                sve_cflags = ['-march=armv8.2-a+sve']
> +                foreach flag: cflags
> +                    if (flag.startswith('-march=')
> +                            or flag.startswith('-mcpu=')
> +                            or flag.startswith('-mtune='))
> +                        continue
> +                    endif
> +                    sve_cflags += flag
> +                endforeach
> +                sve_lib = static_library(libname + '_sve_lib',
> +                        sources_sve,
> +                        dependencies: static_deps,
> +                        include_directories: includes,
> +                        c_args: sve_cflags)
> +                objs += sve_lib.extract_objects(sources_sve)
> +            endif
> +        endif
> +
>          # generate pmdinfo sources by building a temporary
>          # lib and then running pmdinfogen on the contents of
>          # that lib. The final lib reuses the object files and

On the principle, sources_sve must be passed to gen_version_map like
other sources_XXX.


-- 
David Marchand