RE: [PATCH v3] net/mlx5: support live migration

[Raslan Darawsheh <rasland@nvidia.com>]

Hi,

> -----Original Message-----
> From: Rongwei Liu <rongweil@nvidia.com>
> Sent: Wednesday, February 15, 2023 2:04 PM
> To: dev@dpdk.org; Matan Azrad <matan@nvidia.com>; Slava Ovsiienko
> <viacheslavo@nvidia.com>; Ori Kam <orika@nvidia.com>; NBU-Contact-
> Thomas Monjalon (EXTERNAL) <thomas@monjalon.net>
> Cc: Raslan Darawsheh <rasland@nvidia.com>
> Subject: [PATCH v3] net/mlx5: support live migration
> 
> When a DPDK application must be upgraded, the traffic downtime should be
> shortened as much as possible.
> During the migration time, the old application may stay alive while the new
> application is starting and being configured.
> 
> In order to optimize the switch to the new application, the old application
> may need to be aware of the presence of the new application being
> prepared.
> This is achieved with a new API allowing the user to change the new
> application state to standby and active later.
> 
> The added function is trying to apply the new mode to all probed
> mlx5 ports. To make this API simple and easy to use, the same flags have to
> be accepted by all devices.
> 
> This is the scenario of operations in the old and new applications:
> .       device: already configured by the old application
> .       new:    start as active
> .       new:    probe the same device
> .       new:    set as standby
> .       new:    configure the device
> .       device: has configurations from old and new applications
> .       old:    clear its device configuration
> .       device: has only 1 configuration from new application
> .       new:    set as active
> .       device: downtime for connecting all to the new application
> .       old:    shutdown
> 
> The active mode means network handling configurations are programmed to
> the HW immediately, and no behavior changed. This is the default state.
> The standby mode means configurations are queued in the HW.
> If there is no application with active mode, any configuration is effective
> immediately.
> 
> Signed-off-by: Rongwei Liu <rongweil@nvidia.com>
> Acked-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>

Patch applied to next-net-mlx,

Kindest regards,
Raslan Darawsheh