Re: [patch net-next 3/9] mlx4: Implement port type setting via devlink interface

Jiri Pirko
2016-02-23T16:05:01Z

Tue, Feb 23, 2016 at 04:57:17PM CET, hannes@stressinduktion.org wrote:
>On 23.02.2016 16:30, Jiri Pirko wrote:
>>Tue, Feb 23, 2016 at 04:16:11PM CET, hannes@stressinduktion.org wrote:
>>
>><snip>
>>
>>>>>1) is easily solvable, just drop the ifindex style attributes and always
>>>>>force the user to enter the bus and bus-topology id.
>>>>
>>>>But why? Use can easily get that info and map it to devlink index. It
>>>>aligns with nl80211 iface.
>>>>
>>>>Do you really want to do commands like:
>>>>myhost:~$ dl dev show pci_0000:01:00.0
>>>>?
>>>
>>>Yes, exactly I would. I would put them into a boot-up script based on my
>>>system configuration and can be sure it will work the next boot, too, and
>>>adapt them when I replace the hardware or do some configuration changes.
>>>
>>>I think sysadmins or scripts are the primary users of this interface not
>>>kernel developers which switch their settings around all the time, no?
>>
>>I can easily add this to the userspace tool to accept "pci_0000:01:00.0"
>>format and to map it internally to devlink index. No problem.
>
>I argue for this stable topology identifier to be the default. Especially if
>you add device info before the actual module is loaded (this is during
>initramfs, when udev cannot rename devlink names to stable ones), a user has
>to deal with pre-devlink-ids before rename and after. Do you have plans how
>to address that?

You can still access devlink using pci_addr using dl. I don't see a
problem.

>
>Current initramfs for stable interface names uses EUI48 based mac addresses
>most of the time and udev runs then after the pivot_root.
>
>The devlink names can easily be aliases in user space.

I don't want to store them anywhere. I just use "dl" tool and pass the
name there.

>
>Bye,
>Hannes
>
>