[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PATCH] public/io/netif.h: add a new extra type for XDP

On 18.05.20 12:37, Denis Kirjanov wrote:
On 5/18/20, Jürgen Groß <jgross@xxxxxxxx> wrote:
On 18.05.20 11:52, Denis Kirjanov wrote:
On 5/18/20, Jürgen Groß <jgross@xxxxxxxx> wrote:
On 18.05.20 10:24, Denis Kirjanov wrote:
The patch adds a new extra type to be able to diffirentiate
between RX responses on xen-netfront side with the adjusted offset
required for XDP processing.

For Linux the offset value is going to be passed via xenstore.

Why? I can only see disadvantages by using a different communication
I see it like other features passed through xenstore and it requires
less changes to
other structures with the same final result.

This is okay as long there is no Xenstore interaction required when the
interface has been setup completely (i.e. only defining the needed
offset for XDP is fine, enabling/disabling XDP at runtime should not be
done via Xenstore IMO).
I've checked netfront-<--->netback interaction and found no problems with it.
Paul found an issue that the value of the netfront state hasn't been
re-read (during unbind-bind sequence in dom0) and I've fixed it the
patch for the guest

I don't say your variant isn't working, but a feature being switchable
dynamically AND needing a ring page synchronization anyway should IMO
be switched via a specific ring page request.

I might have not the complete picture, so in case you have a good reason
to do it via Xenstore, fine, but "I'm seeing no problem with it" is no
good reason for a specific design decision.

And please, no guest type special casing. Please replace "Linux" by e.g.
"The guest" (with additional tweaking of the following sentence).

Oh, just sent v2. I'll fix a comment.





Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.