Re: VDPA Debug/Statistics

From: Jason Wang
Date: Tue Aug 11 2020 - 22:09:36 EST



On 2020/8/11 下午7:58, Eli Cohen wrote:
On Tue, Aug 11, 2020 at 11:26:20AM +0000, Eli Cohen wrote:
Hi All

Currently, the only statistics we get for a VDPA instance comes from the virtio_net device instance. Since VDPA involves hardware acceleration, there can be quite a lot of information that can be fetched from the underlying device. Currently there is no generic method to fetch this information.

One way of doing this can be to create a the host, a net device for
each VDPA instance, and use it to get this information or do some
configuration. Ethtool can be used in such a case


The problems are:

- vDPA is not net specific
- vDPA should be transparent to host networking stack



I would like to hear what you think about this or maybe you have some other ideas to address this topic.

Thanks,
Eli
Something I'm not sure I understand is how are vdpa instances created on mellanox cards? There's a devlink command for that, is that right?
Can that be extended for stats?

Currently any VF will be probed as VDPA device. We're adding devlink support but I am not sure if devlink is suitable for displaying statistics. We will discuss internally but I wanted to know why you guys think.


I agree with Michael, if it's possible, integrating stats with devlink should be the best. Having another interface with is just for stats looks not good.

Thanks



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