Subject: Re: [net-next 14/15] net/mlx5: Light probe local SFs

From: Jakub Kicinski <[email-masked]>
Date: Sat, 10 Jun 2023 00:01:23 -0700

On Fri,  9 Jun 2023 18:42:53 -0700 Saeed Mahameed wrote:
> In case user wants to configure the SFs, for example: to use only vdpa
> functionality, he needs to fully probe a SF, configure what he wants,
> and afterward reload the SF.
> 
> In order to save the time of the reload, local SFs will probe without
> any auxiliary sub-device, so that the SFs can be configured prior to
> its full probe.

I feel like we talked about this at least twice already, and I keep
saying that the features should be specified when the device is
spawned. Am I misremembering?

Will this patch not surprise existing users? You're changing the
defaults. Does "local" mean on the IPU? Also "lightweight" feels
uncomfortably close to marketing language.

> The defaults of the enable_* devlink params of these SFs are set to
> false.
> 
> Usage example:

Is this a real example? Because we have..

> Create SF:
> $ devlink port add pci/0000:08:00.0 flavour pcisf pfnum 0 sfnum 11

sfnum 11 here

> $ devlink port function set pci/0000:08:00.0/32768 \

then port is 32768

>                hw_addr 00:00:00:00:00:11 state active
> 
> Enable ETH auxiliary device:
> $ devlink dev param set auxiliary/mlx5_core.sf.1 \

and instance is sf.1 

>               name enable_eth value true cmode driverinit
> 
> Now, in order to fully probe the SF, use devlink reload:
> $ devlink dev reload auxiliary/mlx5_core.sf.1
> 
> At this point the user have SF devlink instance with auxiliary device
> for the Ethernet functionality only.