Re: [dpdk-dev] [PATCH] net/i40e: fix incorrect hash look up table

["Chen, BoX C" <box.c.chen@intel.com>]

Tested-by: zhang,xi <xix.zhang@intel.com>

Regards,
Chen Bo

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Shougang Wang
> Sent: July 15, 2020 14:35
> To: dev@dpdk.org
> Cc: Xing, Beilei <beilei.xing@intel.com>; Guo, Jia <jia.guo@intel.com>; Wang,
> ShougangX <shougangx.wang@intel.com>; stable@dpdk.org
> Subject: [dpdk-dev] [PATCH] net/i40e: fix incorrect hash look up table
> 
> The hash look up table(LUT) will not be initializing when starting testpmd with
> --disable-rss. So that some queues in LUT will be invalid if rx queues is less
> than last time. When enable RSS by creating RSS rule, some packets will not
> be into the valid queues.
> This patch fixes this issue by initializing the LUT when creating an RSS rule.
> 
> Fixes: feaae285b342 ("net/i40e: support hash configuration in RSS flow")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Shougang Wang <shougangx.wang@intel.com>
> ---
>  drivers/net/i40e/i40e_ethdev.c | 52
> ++++++++++++++++++++++++++++++++++
>  1 file changed, 52 insertions(+)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
> index 393b5320f..2a92bd8ef 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -13070,6 +13070,49 @@ i40e_rss_conf_init(struct
> i40e_rte_flow_rss_conf *out,
>  	return 0;
>  }
> 
> +static int
> +i40e_rss_init_lut(struct i40e_pf *pf)
> +{
> +	struct i40e_hw *hw = I40E_PF_TO_HW(pf);
> +	uint32_t lut = 0;
> +	uint16_t j, num;
> +	uint32_t i;
> +
> +	/*
> +	 * If both VMDQ and RSS enabled, not all of PF queues are configured.
> +	 * It's necessary to calculate the actual PF queues that are configured.
> +	 */
> +	if (pf->dev_data->dev_conf.rxmode.mq_mode &
> ETH_MQ_RX_VMDQ_FLAG)
> +		num = i40e_pf_calc_configured_queues_num(pf);
> +	else
> +		num = pf->dev_data->nb_rx_queues;
> +
> +	num = RTE_MIN(num, I40E_MAX_Q_PER_TC);
> +	PMD_INIT_LOG(INFO, "Max of contiguous %u PF queues are
> configured",
> +		     num);
> +
> +	if (num == 0) {
> +		PMD_INIT_LOG(ERR,
> +			"No PF queues are configured to enable RSS for
> port %u",
> +			pf->dev_data->port_id);
> +		return -ENOTSUP;
> +	}
> +
> +	if (pf->adapter->rss_reta_updated == 0) {
> +		for (i = 0, j = 0; i < hw->func_caps.rss_table_size; i++, j++) {
> +			if (j == num)
> +				j = 0;
> +			lut = (lut << 8) | (j & ((0x1 <<
> +				hw->func_caps.rss_table_entry_width) - 1));
> +			if ((i & 3) == 3)
> +				I40E_WRITE_REG(hw, I40E_PFQF_HLUT(i >>
> 2),
> +					       rte_bswap32(lut));
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  /* Write HENA register to enable hash */  static int  i40e_rss_hash_set(struct
> i40e_pf *pf, struct i40e_rte_flow_rss_conf *rss_conf) @@ -13318,12
> +13361,21 @@ static int  i40e_rss_enable_hash(struct i40e_pf *pf,
>  		struct i40e_rte_flow_rss_conf *conf)
>  {
> +	enum rte_eth_rx_mq_mode mq_mode =
> +pf->dev_data->dev_conf.rxmode.mq_mode;
>  	struct i40e_rte_flow_rss_conf *rss_info = &pf->rss_info;
>  	struct i40e_rte_flow_rss_conf rss_conf;
> 
>  	if (!(conf->conf.types & pf->adapter->flow_types_mask))
>  		return -ENOTSUP;
> 
> +	/*
> +	 * If the RSS is disabled before this, the LUT is uninitialized.
> +	 * So it is necessary to initialize it here.
> +	 */
> +	if (!(mq_mode & ETH_MQ_RX_RSS_FLAG) && !pf-
> >rss_info.conf.queue_num)
> +		if (i40e_rss_init_lut(pf))
> +			return -ENOTSUP;
> +
>  	memset(&rss_conf, 0, sizeof(rss_conf));
>  	rte_memcpy(&rss_conf, conf, sizeof(rss_conf));
> 
> --
> 2.17.1