[dpdk-dev] [fix probabilistic failure of i40evf initialization] net/i40e: fix probabilistic failure of i40evf initialization

[Zhang, Qi Z]

Hi: 
please following guideline.
https://doc.dpdk.org/guides/contributing/patches.html

> -----Original Message-----
> From: chenqiming2018 at 163.com <chenqiming2018 at 163.com>
> Sent: Tuesday, March 9, 2021 11:41 PM
> To: dev at dpdk.org
> Cc: chenqiming2018 at 163.com; Xing, Beilei <beilei.xing at intel.com>; Zhang,
> Qi Z <qi.z.zhang at intel.com>
> Subject: [fix probabilistic failure of i40evf initialization] net/i40e: fix
> probabilistic failure of i40evf initialization
> 
> From: Qiming Chen <chenqiming2018 at 163.com>
> 
>     The d2146nt chip integrates the x722 controller. The i40e.ko version is
> 2.9.21, and the firmware version is Intel’s customized version 4.3. It has been
> communicated with Intel Steven. The version is compatible. Each PF virtual
> place has 16 VFs, and there are 2 Each process takes over several VF ports, and
> there is no VF kernel driver on the host. In an embedded environment,
> repeated single board restarts may cause VF initialization failure.
>     By checking the log, it can be confirmed that the
> i40evf_check_vf_reset_done function returns an error. Through a horizontal
> comparison with the iavf.ko code, it is found that the iavf kernel driver is
> implemented as a loop 20 times, and the vf status is checked for 5 seconds
> each time to increase the reliability of the vf initialization.
>     Try to modify the align iavf.ko, repeat the test and reproduce, and find
> that the problem no longer exists. Although the probability is relatively small,
> the result is more serious, so it is recommended to modify it.
> 
> Signed-off-by: Qiming Chen <chenqiming2018 at 163.com>
> ---
>  drivers/net/i40e/i40e_ethdev_vf.c | 20 ++++++++++++++++----
>  1 file changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev_vf.c
> b/drivers/net/i40e/i40e_ethdev_vf.c
> index 0c9bd8d2c..8bfbb1153 100644
> --- a/drivers/net/i40e/i40e_ethdev_vf.c
> +++ b/drivers/net/i40e/i40e_ethdev_vf.c
> @@ -42,7 +42,8 @@
>  /* busy wait delay in msec */
>  #define I40EVF_BUSY_WAIT_DELAY 10
>  #define I40EVF_BUSY_WAIT_COUNT 50
> -#define MAX_RESET_WAIT_CNT     20
> +#define I40EVF_AQ_MAX_ERR      20
> +#define MAX_RESET_WAIT_CNT     500
> 
>  #define I40EVF_ALARM_INTERVAL 50000 /* us */
> 
> @@ -1217,7 +1218,7 @@ i40evf_check_vf_reset_done(struct rte_eth_dev
> *dev)
>  		if (reset == VIRTCHNL_VFR_VFACTIVE ||
>  		    reset == VIRTCHNL_VFR_COMPLETED)
>  			break;
> -		rte_delay_ms(50);
> +		rte_delay_ms(10);
>  	}
> 
>  	if (i >= MAX_RESET_WAIT_CNT)
> @@ -1276,9 +1277,20 @@ i40evf_init_vf(struct rte_eth_dev *dev)
>  		goto err;
>  	}
> 
> -	err = i40evf_check_vf_reset_done(dev);
> -	if (err)
> +	for (i = 0; i < I40EVF_AQ_MAX_ERR; i++) {
> +		err = i40evf_check_vf_reset_done(dev);
> +		if (err) {
> +			PMD_INIT_LOG(WARNING, "Device is still reset: %d %d", err, i);
> +			continue;
> +		} else {
> +			break;
> +		}
> +	}
> +
> +	if (i == I40EVF_AQ_MAX_ERR) {
> +		PMD_INIT_LOG(ERR, "Device check vf reset status failed");
>  		goto err;
> +	}
> 
>  	i40e_init_adminq_parameter(hw);
>  	err = i40e_init_adminq(hw);
> --
> 2.30.1.windows.1