On Wed, Apr 18, 2018 at 01:55:41AM +0000, chenchanghu wrote: > Hi, Adrien Mazarguil, > > Thanks for your reply very much. > > It means in our tests, when ‘ifconfig eth7 down’, the expect result is the > bond primary netdevice will switch to eth8. > > However, we find the bond primary is not changed to eth8 in 19 times of 20 > time tests., and it means the dpdk bond doesn't receive an LSC interrupt > signal. > > In our test, the netdevice is mlx4 VF in Virtual Machine, which netdevice is > direct through by SR-IOV.
I overlooked this part, I'm not sure VFs impact link status on the DPDK side since they can't really bring it down. Regardless, you should have encountered an identical behavior 20 out of 20 times otherwise there could be a bug in the DPDK version you're using. > We also test mlx4 PF in Physical Machine, when ‘ifconfig eth7 down’, the > test esult is the bond primary netdevice switched to eth8. Right, PF has authority over link status, this is expected as documented. > Quesetion: > > Is it related with SR-IOV direct through ? For example, the VF netdevice > status changed, but it will not send an LSC interruput signal. > > Looking forward to your any reply. To summarize, updating the link status of a netdevice associated with a VF shouldn't impact a DPDK application. On the other hand updating it on a netdevice associated with PF will impact all VFs and their applications. Please check again with a more recent DPDK version (e.g. 18.02). If you manage to get a consistent behavior every time, it means a bug is present in in 16.04. > -----邮件原件----- > 发件人: Adrien Mazarguil [mailto:adrien.mazarg...@6wind.com] > 发送时间: 2018年4月17日 18:08 > 收件人: chenchanghu <chenchan...@huawei.com> > 抄送: dev@dpdk.org; nelio.laranje...@6wind.com; Zhoujingbin (Robin, Cloud > Networking) <zhoujing...@huawei.com>; Zhoulei (G) <stone.z...@huawei.com>; > yangleyuan <yangley...@huawei.com> > 主题: Re: [disscussion] A problem about dpdk backup-mode bond switching with > mlx4 VF devices > > > > On Tue, Apr 17, 2018 at 06:40:20AM +0000, chenchanghu wrote: > > > > > > Hi, > > > When I used the mlx4 pmd, I meet a problem about mlx4 VF bond > > switching which bond mod is backup-mode . The detail test is descripted > > below. > > > 1.Test environmemt infomation: > > > a. Linux distribution: CentOS > > > b. dpdk version: dpdk-16.04 > > > c. Ethernet device : mlx4 VF > > > d. pmd info: mlx4 poll-mode-driver > > > > > > 2.Test step: > > > a. we bond the mlx4 VF Ethernet device eth7,eth8 into backup-mode by dpdk > > application. Eth7 and eth8 are both active, and eth7 is the primary device. > > > b. As we know, the device eth7 , eth8 are also visible by kernel driver > > mlx4_en. > > > c. Then we config the Ethernet device eth7 down by the command ' ifconfig > > eth7 down', the expect result is the bond primary device will not switch. > > > d. However we find the dpdk bond primary device switch to eth8 by dpdk > > maintenance interface one time in all 20 test times. > > > > > > 3.Question: > > > Is the VF up or down State of kernel interface has some relations to > > user-space state? For example, when ifconfig eth7 down, and the user-space > > will change to down state too. > > > > Yes, this is expected. Netdevices and the mlx4 DPDK PMD share a common link > status. Bringing a netdevice down causes link status to be down for all its > users. This behavior is documented [1]. > > > > [1] http://dpdk.org/doc/guides/nics/mlx4.html#run-time-configuration > > > > -- > > Adrien Mazarguil > > 6WIND -- Adrien Mazarguil 6WIND
