[dpdk-dev] [PATCH 20.11 00/12] add max SIMD bitwidth to EAL

[Stephen Hemminger]

On Fri,  7 Aug 2020 16:58:47 +0100
Ciara Power <ciara.power at intel.com> wrote:

> A number of components in DPDK have optional AVX-512 or other vector
> code paths which can be selected at runtime. Rather than having each
> component provide its own mechanism to select a code path, this patchset
> adds support for a single setting to control what code paths are used.
> This can be used to enable some non-default code paths e.g. ones using
> AVX-512, but also to limit the code paths to certain vector widths, or
> to scalar code only, which is useful for testing.
> 
> The max SIMD bitwidth setting can be set by the app itself through use of
> the available API, or can be overriden by a commandline argument passed by
> the user.
> 
> Ciara Power (12):
>   eal: add max SIMD bitwidth
>   eal: add default SIMD bitwidth values
>   net/i40e: add checks for max SIMD bitwidth
>   net/axgbe: add checks for max SIMD bitwidth
>   net/bnxt: add checks for max SIMD bitwidth
>   net/enic: add checks for max SIMD bitwidth
>   net/fm10k: add checks for max SIMD bitwidth
>   net/iavf: add checks for max SIMD bitwidth
>   net/ice: add checks for max SIMD bitwidth
>   net/ixgbe: add checks for max SIMD bitwidth
>   net/mlx5: add checks for max SIMD bitwidth
>   net/virtio: add checks for max SIMD bitwidth
> 
>  drivers/net/axgbe/axgbe_rxtx.c             |  3 +-
>  drivers/net/bnxt/bnxt_ethdev.c             |  6 ++-
>  drivers/net/enic/enic_rxtx_vec_avx2.c      |  3 +-
>  drivers/net/fm10k/fm10k_ethdev.c           | 11 ++--
>  drivers/net/i40e/i40e_rxtx.c               | 19 ++++---
>  drivers/net/iavf/iavf_rxtx.c               | 16 +++---
>  drivers/net/ice/ice_rxtx.c                 | 20 ++++---
>  drivers/net/ixgbe/ixgbe_rxtx.c             |  7 ++-
>  drivers/net/mlx5/mlx5_ethdev.c             |  3 +-
>  drivers/net/virtio/virtio_ethdev.c         | 12 +++--
>  lib/librte_eal/arm/include/rte_vect.h      |  2 +
>  lib/librte_eal/common/eal_common_options.c | 63 ++++++++++++++++++++++
>  lib/librte_eal/common/eal_internal_cfg.h   |  8 +++
>  lib/librte_eal/common/eal_options.h        |  2 +
>  lib/librte_eal/include/generic/rte_vect.h  |  2 +
>  lib/librte_eal/include/rte_eal.h           | 31 +++++++++++
>  lib/librte_eal/ppc/include/rte_vect.h      |  2 +
>  lib/librte_eal/rte_eal_version.map         |  4 ++
>  lib/librte_eal/x86/include/rte_vect.h      |  2 +
>  19 files changed, 184 insertions(+), 32 deletions(-)
> 

This looks useful, could you add some documentation on rationale
and how you expect application to set it.