On Fri, Jul 25, 2025 at 12:49:10PM +0000, Ciara Loftus wrote:
> From: Bruce Richardson <bruce.richard...@intel.com>
>
> A common need within the drivers is to select between SSE, AVX2 and
> AVX-512 code paths. Provide a common function which helps with this
> decision making, that returns the max simd bandwidth based on any
> user configured maximums and available CPU flags.
>
> Signed-off-by: Bruce Richardson <bruce.richard...@intel.com>
> Signed-off-by: Ciara Loftus <ciara.lof...@intel.com>
> ---
> drivers/net/intel/common/rx_vec_x86.h | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)
>
> diff --git a/drivers/net/intel/common/rx_vec_x86.h
> b/drivers/net/intel/common/rx_vec_x86.h
> index 3d7343b1ff..314fa24b41 100644
> --- a/drivers/net/intel/common/rx_vec_x86.h
> +++ b/drivers/net/intel/common/rx_vec_x86.h
> @@ -346,4 +346,27 @@ ci_rxq_rearm(struct ci_rx_queue *rxq, const enum
> ci_rx_vec_level vec_level)
> rte_write32_wc(rte_cpu_to_le_32(rx_id), rxq->qrx_tail);
> }
>
> +#ifdef CC_AVX512_SUPPORT
> +#define X86_MAX_SIMD_BITWIDTH (rte_vect_get_max_simd_bitwidth())
> +#else
> +#define X86_MAX_SIMD_BITWIDTH RTE_MIN(256, rte_vect_get_max_simd_bitwidth())
> +#endif /* CC_AVX512_SUPPORT */
> +
> +static inline enum rte_vect_max_simd
> +ci_get_x86_max_simd_bitwidth(void)
> +{
> + int ret = RTE_VECT_SIMD_DISABLED;
> + int simd = X86_MAX_SIMD_BITWIDTH;
> +
> + if (simd >= 512 && rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX512F) == 1 &&
> + rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX512BW) == 1)
> + ret = RTE_VECT_SIMD_512;
> + else if (simd >= 256 && (rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX2) ==
> 1 ||
> + rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX512F) == 1))
Don't need to check the AVX512 flag here.
> + ret = RTE_VECT_SIMD_256;
> + else if (simd >= 128)
> + ret = RTE_VECT_SIMD_128;
> + return ret;
> +}
> +
> #endif /* _COMMON_INTEL_RX_VEC_X86_H_ */
> --
> 2.34.1
>
