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Date:   Thu, 3 Sep 2020 12:47:19 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Jiri Pirko <jiri@resnulli.us>
Cc:     Moshe Shemesh <moshe@nvidia.com>,
        Moshe Shemesh <moshe@mellanox.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jiri Pirko <jiri@mellanox.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next RFC v3 01/14] devlink: Add reload action option
 to devlink reload command
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On Thu, 3 Sep 2020 07:57:29 +0200 Jiri Pirko wrote:
> Wed, Sep 02, 2020 at 05:30:25PM CEST, kuba@kernel.org wrote:
> >On Wed, 2 Sep 2020 11:46:27 +0200 Jiri Pirko wrote:  
> >> >? Do we need such change there too or keep it as is, each action by itself
> >> >and return what was performed ?    
> >> 
> >> Well, I don't know. User asks for X, X should be performed, not Y or Z.
> >> So perhaps the return value is not needed.
> >> Just driver advertizes it supports X, Y, Z and the users says:
> >> 1) do X, driver does X
> >> 2) do Y, driver does Y
> >> 3) do Z, driver does Z
> >> [
> >> I think this kindof circles back to the original proposal...  
> >
> >Why? User does not care if you activate new devlink params when
> >activating new firmware. Trust me. So why make the user figure out
> >which of all possible reset option they should select? If there is 
> >a legitimate use case to limit what is reset - it should be handled
> >by a separate negative attribute, like --live which says don't reset
> >anything.  
> 
> I see. Okay. Could you please sum-up the interface as you propose it?

What I proposed on v1, pass requested actions as a bitfield, driver may
perform more actions, we can return performed actions in the response.

Then separate attribute to carry constraints for the request, like
--live.

I'd think the supported actions in devlink_ops would be fine as a
bitfield, too. Combinations are often hard to capture in static data.