[dpdk-stable] [PATCH 20.11] net/i40e: extend the polling times of vf reset

[Xing, Beilei]

> -----Original Message-----
> From: Qiming Chen <chenqiming_huawei at 163.com>
> Sent: Monday, September 6, 2021 3:14 PM
> To: stable at dpdk.org
> Cc: Xing, Beilei <beilei.xing at intel.com>; Qiming Chen
> <chenqiming_huawei at 163.com>
> Subject: [PATCH 20.11] net/i40e: extend the polling times of vf reset
Besides, the title should be net/i40evf: xxxx
This comment is for all you fix patches for i40evf.

> 
> In the embedded RTOS environment, the x722 controller Ethernet card of the
> d2146nt chip, the vfio user mode driver takes over 8 vf ports in turn, but
> i40evf_check_vf_reset_done will probably fail.
> 
> This issue has been discussed with intel&dpdk experts for 3 rounds before,
> and the version matching is no problem, and there is no substantial progress.
> The official website contacted external experts, but there was no response
> afterwards. Learning from the implementation of the i40evf kernel driver
> locally, after modifying the polling time from 1 second to 5s, the repeated
> restart process took over the start port test, and it was found that this
> probability was reduced to an order of magnitude acceptable to the user.
> 
> The patch cannot fundamentally solve the failure problem, but it greatly
> slows down the probability of the problem. The modification is based on the
> i40evf kernel driver.
> 
> Fixes: 5c9222058df7 ("i40e: move to drivers/net/")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Qiming Chen <chenqiming_huawei at 163.com>
> ---
>  drivers/net/i40e/i40e_ethdev_vf.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev_vf.c
> b/drivers/net/i40e/i40e_ethdev_vf.c
> index f64db72e9a..924da8dfb4 100644
> --- a/drivers/net/i40e/i40e_ethdev_vf.c
> +++ b/drivers/net/i40e/i40e_ethdev_vf.c
> @@ -42,7 +42,7 @@
>  /* busy wait delay in msec */
>  #define I40EVF_BUSY_WAIT_DELAY 10
>  #define I40EVF_BUSY_WAIT_COUNT 50
> -#define MAX_RESET_WAIT_CNT     20
> +#define MAX_RESET_WAIT_CNT     100
> 
>  #define I40EVF_ALARM_INTERVAL 50000 /* us */
> 
> --
> 2.30.1.windows.1