[PATCH] net/iavf: set interrupt throttling register

[Bruce Richardson]

On Mon, Oct 05, 2026 at 12:06:13PM +0100, Bruce Richardson wrote:
> The interrupt throttling register(ITR) bank 0 value is set to 2, but
> to ensure best performance across all systems also set the bank 1 value
> to match.
> 
> Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
> ---
>  drivers/net/intel/iavf/iavf_ethdev.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
>

Further testing has indicated that this patch is simply working around a
config issue on kernel driver side[1] and should not be necessary in DPDK.

Dropping as rejected in patchwork.

/Bruce

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fb096882095e5a8d6b5159e43793d4a38a0c5b1f
 
> diff --git a/drivers/net/intel/iavf/iavf_ethdev.c b/drivers/net/intel/iavf/iavf_ethdev.c
> index a8abe0154c..dc3cea0b95 100644
> --- a/drivers/net/intel/iavf/iavf_ethdev.c
> +++ b/drivers/net/intel/iavf/iavf_ethdev.c
> @@ -899,10 +899,7 @@ static int iavf_config_rx_queues_irqs(struct rte_eth_dev *dev,
>  				       (0 << IAVF_VFINT_DYN_CTLN1_ITR_INDX_SHIFT) |
>  				       IAVF_VFINT_DYN_CTLN1_WB_ON_ITR_MASK |
>  				       (2UL << IAVF_VFINT_DYN_CTLN1_INTERVAL_SHIFT));
> -			/* debug - check for success! the return value
> -			 * should be 2, offset is 0x2800
> -			 */
> -			/* IAVF_READ_REG(hw, IAVF_VFINT_ITRN1(0, 0)); */
> +			IAVF_WRITE_REG(hw, IAVF_VFINT_ITRN1(1, vf->msix_base - 1), 2);
>  		} else {
>  			/* If no WB_ON_ITR offload flags, need to set
>  			 * interrupt for descriptor write back.
> -- 
> 2.53.0
>