[PATCH v6] sched: enable CMAN at runtime

[Danilewicz, MarcinX]

Hi Cristian,

<SNIP>
> The code changes in the library (rte-sched.c) look good to me, but I do have
> some questions for the qos_sched app and the Soft NIC driver on how CMAN
> gets enabled/disabled.
That was open q from start. We finally found a time to discuss this.
 
> How do we control whether congestion management (CMAN) should be
> disabled on enabled (WRED/PIE)? It looks to me like you are always enabling
> WRED by default, which is incorrect: we should have CMAN disabled by
> default (in init.c).
Cannot disagree.

> My preferred way to configure CMAN is:
> a) CMAN should be disabled by default
> b) If the CMAN parameters get configured in the profile.cfg, then and only
> then CMAN should be enabled according to the configuration.
OK

> In init.c, we can safely set the subport CMAN parameters to NULL as the
> built-in default when the profile.cfg is not provided, so we can safely remove
> the WRED params from there.
Agree

> In cfg_file.c, we need to have a good way to disable/enable CMAN.
Let me provide something and then you will have a look at it.

> In profile.cfg, please remove the WRED lines as opposed to commenting
> them out.
OK

> Is this OK with you?
That's perfectly fine and looks good.
 
> Also, have you tested the qos_sched app and the Soft NIC driver with all 3
> configuration files?
Obviously yes, but not the last time. And I will repeat such testing as the last thing.

Kind Regards,
/Marcin