Re: [net-next-2.6 PATCH 1/2] Add ndo_set_vf_port_profile

[Scott Feldman <scofeldm@cisco.com>]

On 4/26/10 12:27 PM, "Scott Feldman" <scofeldm@cisco.com> wrote:
> On 4/24/10 12:19 AM, "David Miller" <davem@davemloft.net> wrote:
>> Also, I think it's reasonable to fetch the current profile in use, so
>> GETLINK ought to report these things.  To make it generic we can
>> maintain the settings given to us in software, hung off of the netdev
>> struct, and simply report that during GETLINK.
> 
> We'd need an array of struct ifla_vf_port_profile hanging off of netdev, one
> element for each VF.  That seems like a lot of mem hanging off of netdev,
> and we'd have to define a MAX_VF to size the array.  How about a
> ndo_get_vf_port_profile() that the netdev fills in, and the netdev keeps the
> data in it's private area?  That's how ndo_get_vf_config() is working.

Hmmm....even that isn't so nice because the port-profile info for all VFs is
going to get stuffed into the RTM_GETLINK skb, and I assume there are limits
on the skb return size.

Here's a proposal:

Currently we have RTM_GETLINK for

    ip link show [ DEVICE ]

This dumps everything for the DEVICE including info for each VF.  Let's
modify RTM_GETLINK to look like this:

    ip link show [ DEVICE [ vf NUM] ]

If you don't give the optional vf NUM you get base dump on DEVICE.  If you
give vf NUM, you get the VF-specific dump.  This scales much better with the
number of VFs.  

(Number of VFs can easily be > 128 in some designs).

Comments?

-scott