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Subject: Re: [PATCH net-next RFC v2 01/13] devlink: Add reload action option
 to devlink reload command
To:     Jakub Kicinski <kuba@kernel.org>,
        Moshe Shemesh <moshe@mellanox.com>
CC:     "David S. Miller" <davem@davemloft.net>,
        Jiri Pirko <jiri@mellanox.com>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
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From:   Moshe Shemesh <moshe@nvidia.com>
Message-ID: <9fbad1d6-7052-225a-7d62-9d29548d6342@nvidia.com>
Date:   Tue, 18 Aug 2020 12:06:13 +0300
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On 8/17/2020 7:16 PM, Jakub Kicinski wrote:
>
> On Mon, 17 Aug 2020 12:37:40 +0300 Moshe Shemesh wrote:
>> Add devlink reload action to allow the user to request a specific reload
>> action. The action parameter is optional, if not specified then devlink
>> driver re-init action is used (backward compatible).
>> Note that when required to do firmware activation some drivers may need
>> to reload the driver. On the other hand some drivers may need to reset
>> the firmware to reinitialize the driver entities.
> See, this is why I wanted to keep --live as a separate option.
> Normally the driver is okay to satisfy more actions than requested,
> e.g. activate FW even if only driver_reinit was requested.
>
> fw_live_patch does not have this semantics, it explicitly requires
> driver to not impact connectivity much. No "can do more resets than
> requested" here. Hence the --live part would be better off as a
> separate argument (at least in uAPI, the in-kernel interface we can
> change later if needed).


Yes, it does have a different semantics, kind of no reset allowed.

On the other hand, it is not related to driver_reinit, only fw_activate.

So the uAPI should be:

 =C2=A0=C2=A0=C2=A0 devlink dev reload DEV [ netns { PID | NAME | ID } ] [ =
action {=20
driver_reinit | fw_activate [--live] } ]

Or maybe better than "live" say explicitly "no reset":

 =C2=A0=C2=A0=C2=A0 devlink dev reload DEV [ netns { PID | NAME | ID } ] [ =
action {=20
driver_reinit | fw_activate [--no_reset] } ]


>> Reload actions supported are:
>> driver_reinit: driver entities re-initialization, applying devlink-param
>>                 and devlink-resource values.
>> fw_activate: firmware activate.
>> fw_live_patch: firmware live patching.