Re: [PATCH 0/4] fix issues with using AVX-512 drivers on 32-bit

[Bruce Richardson <bruce.richardson@intel.com>]

On Mon, Sep 30, 2024 at 04:57:21PM +0100, Bruce Richardson wrote:
> On Mon, Sep 30, 2024 at 05:38:44PM +0200, David Marchand wrote:
> > On Fri, Sep 6, 2024 at 4:11 PM Bruce Richardson
> > <bruce.richardson@intel.com> wrote:
> > >
> > > The AVX-512 copy code in multiple drivers was incorrect for 32-bit as it
> > > assumed that each pointer was always 8B in size.
> > >
> > > Bruce Richardson (4):
> > >   net/i40e: fix AVX-512 pointer copy on 32-bit
> > >   net/ice: fix AVX-512 pointer copy on 32-bit
> > >   net/iavf: fix AVX-512 pointer copy on 32-bit
> > >   common/idpf: fix AVX-512 pointer copy on 32-bit
> > >
> > >  drivers/common/idpf/idpf_common_rxtx_avx512.c | 7 +++++++
> > >  drivers/net/i40e/i40e_rxtx_vec_avx512.c       | 7 +++++++
> > >  drivers/net/iavf/iavf_rxtx_vec_avx512.c       | 7 +++++++
> > >  drivers/net/ice/ice_rxtx_vec_avx512.c         | 7 +++++++
> > >  4 files changed, 28 insertions(+)
> > 
> > Sorry, not directly related to this series, but as I was checking some
> > AVX512 patch, I suspect some drivers are missing runtime checks for
> > availability of some AVX512 instructions:
> > 
> > $ for meson in $(git grep -l __AVX512[^_]*__
> > 'drivers/**/meson.build'); do dir=$(dirname $meson); for flag in $(git
> > grep -ho __AVX512[^_]*__ $dir | sort -u); do flag=${flag%%__};
> > flag=${flag##__}; git grep -ql
> > rte_cpu_get_flag_enabled.RTE_CPUFLAG_$flag $dir || echo
> > RTE_CPUFLAG_$flag check missing in $dir; done; done
> > 
> > RTE_CPUFLAG_AVX512BW check missing in drivers/common/idpf
> > RTE_CPUFLAG_AVX512DQ check missing in drivers/common/idpf
> > RTE_CPUFLAG_AVX512F check missing in drivers/common/idpf
> > RTE_CPUFLAG_AVX512VL check missing in drivers/net/i40e
> > RTE_CPUFLAG_AVX512VL check missing in drivers/net/ice
> > 
> > Maybe some flags are implictly available... worth a confirmation from
> > Intel in any case from my pov.
> > 
> 
> I think it would be good practice to explicitly check for all the AVX-512
> extensions actually used. Ideally, as a cleanup, we should probably check
> for those listed (f, bw, dq and vl) once early in the config and reuse that
> value throughout the build, rather than having each and every PMD
> continually check them.
> 
Draft patchset for this now submitted to dev list [1]. Reviews and feedback
welcome, as always!

/Bruce

[1] https://patches.dpdk.org/project/dpdk/list/?series=33188