Re: [dpdk-dev] [PATCH] net/ixgbe: update data->eth_link status on start

[Chas Williams <3chas3@gmail.com>]

On Fri, Mar 30, 2018 at 12:30 PM, Zhang, Helin <helin.zhang@intel.com> wrote:
>
>
>> -----Original Message-----
>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Chas Williams
>> Sent: Wednesday, February 14, 2018 6:56 AM
>> To: dev@dpdk.org
>> Cc: Lu, Wenzhuo; Ananyev, Konstantin; Charles (Chas) Williams
>> Subject: [dpdk-dev] [PATCH] net/ixgbe: update data->eth_link status on start
>>
>> From: "Charles (Chas) Williams" <chas3@att.com>
>>
>> dev->data->eth_link isn't updated until the first interrupt.  If a
>> link is carrier down, then this interrupt may never happen.  Before we finished
>> starting the PMD, call ixgbe_dev_link_update() to ensure we have a valid status.
>>
>> Signed-off-by: Chas Williams <chas3@att.com>
>> ---
>>  drivers/net/ixgbe/ixgbe_ethdev.c | 4 ++++
>>  1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c
>> b/drivers/net/ixgbe/ixgbe_ethdev.c
>> index 37eb668..27d29dc 100644
>> --- a/drivers/net/ixgbe/ixgbe_ethdev.c
>> +++ b/drivers/net/ixgbe/ixgbe_ethdev.c
>> @@ -2666,6 +2666,8 @@ ixgbe_dev_start(struct rte_eth_dev *dev)
>>       if (err)
>>               goto error;
>>
>> +     ixgbe_dev_link_update(dev, 0);
> It is called in rte_eth_dev_start() if lsc is not enabled,
> and it is not needed here to avoid any duplication.
> BTW, did you see any issue or just check the code? Thanks!

Yes, I see an issue with bonding.  If LSC is enabled, then link_status
isn't set until the first interrupt to update the link status.  If a
link is down, this interrupt may never happen result in link_status
being somewhat undefined.

>
> /Helin
>
>> +
>>  skip_link_setup:
>>
>>       if (rte_intr_allow_others(intr_handle)) { @@ -5033,6 +5035,8 @@
>> ixgbevf_dev_start(struct rte_eth_dev *dev)
>>
>>       ixgbevf_dev_rxtx_start(dev);
>>
>> +     ixgbevf_dev_link_update(dev, 0);
>> +
>>       /* check and configure queue intr-vector mapping */
>>       if (rte_intr_cap_multiple(intr_handle) &&
>>           dev->data->dev_conf.intr_conf.rxq) {
>> --
>> 2.9.5
>