net/i40e: fix DCB init issue

  Stopping lldp is necessary for DPDK, but it will cause DCB init failed.
For kernel shared code, the prerequisite for successful initialization
of DCB is that LLDP is enabled. This patch starts lldp before DCB init
and stops it when finish init.

Fixes: a8e84b22bd55 ("net/i40e/base: support persistent LLDP")
Cc: stable@dpdk.org

Signed-off-by: Shougang Wang <shougangx.wang@intel.com>
---
 drivers/net/i40e/i40e_ethdev.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)
  

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Shougang Wang
> Sent: Thursday, March 5, 2020 4:41 PM
> To: dev@dpdk.org
> Cc: Yang, Qiming <qiming.yang@intel.com>; Xing, Beilei
> <beilei.xing@intel.com>; Wang, ShougangX <shougangx.wang@intel.com>;
> stable@dpdk.org
> Subject: [dpdk-dev] [PATCH] net/i40e: fix DCB init issue
> 
> Stopping lldp is necessary for DPDK, but it will cause DCB init failed.
> For kernel shared code, the prerequisite for successful initialization of DCB is
> that LLDP is enabled. This patch starts lldp before DCB init and stops it when
> finish init.
> 
> Fixes: a8e84b22bd55 ("net/i40e/base: support persistent LLDP")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Shougang Wang <shougangx.wang@intel.com>
> ---
>  drivers/net/i40e/i40e_ethdev.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
> index 9fbda1c34..9f37662f8 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -11669,11 +11669,9 @@ i40e_dcb_init_configure(struct rte_eth_dev *dev,
> bool sw_dcb)
>  	 * LLDP MIB change event.
>  	 */
>  	if (sw_dcb == TRUE) {
> -		if (i40e_need_stop_lldp(dev)) {
> -			ret = i40e_aq_stop_lldp(hw, TRUE, TRUE, NULL);
> -			if (ret != I40E_SUCCESS)
> -				PMD_INIT_LOG(DEBUG, "Failed to stop lldp");
> -		}

It's better to add some comment here, so easy for other people to understand the purpose.
Otherwise

Acked-by: Qi Zhang <qi.z.zhang@intel.com>



> +		ret = i40e_aq_start_lldp(hw, true, NULL);
> +		if (ret != I40E_SUCCESS)
> +			PMD_INIT_LOG(DEBUG, "Failed to start lldp");

> 
>  		ret = i40e_init_dcb(hw, true);
>  		/* If lldp agent is stopped, the return value from @@ -11718,6
> +11716,12 @@ i40e_dcb_init_configure(struct rte_eth_dev *dev, bool sw_dcb)
>  				ret, hw->aq.asq_last_status);
>  			return -ENOTSUP;
>  		}
> +
> +		if (i40e_need_stop_lldp(dev)) {
> +			ret = i40e_aq_stop_lldp(hw, true, true, NULL);
> +			if (ret != I40E_SUCCESS)
> +				PMD_INIT_LOG(DEBUG, "Failed to stop lldp");
> +		}
>  	} else {
>  		ret = i40e_aq_start_lldp(hw, true, NULL);
>  		if (ret != I40E_SUCCESS)
> --
> 2.17.1