Re: [PATCH net 1/1] igc: Fix double reset adapter triggered from a single taprio cmd

[Vladimir Oltean <vladimir.oltean@nxp.com>]

On Wed, Jun 26, 2024 at 09:19:12AM +0800, Abdul Rahim, Faizal wrote:
> Added Vladimir and Husaini in CC.
> 
> On 25/6/2024 4:26 pm, Faizal Rahim wrote:
> > Following the implementation of "igc: Add TransmissionOverrun counter"
> > patch, when a taprio command is triggered by user, igc processes two
> > commands: TAPRIO_CMD_REPLACE followed by TAPRIO_CMD_STATS. However, both
> > commands unconditionally pass through igc_tsn_offload_apply() which
> > evaluates and triggers reset adapter. The double reset causes issues in
> > the calculation of adapter->qbv_count in igc.
> > 
> > TAPRIO_CMD_REPLACE command is expected to reset the adapter since it
> > activates qbv. It's unexpected for TAPRIO_CMD_STATS to do the same
> > because it doesn't configure any driver-specific TSN settings. So, the
> > evaluation in igc_tsn_offload_apply() isn't needed for TAPRIO_CMD_STATS.
> > 
> > To address this, commands parsing are relocated to
> > igc_tsn_enable_qbv_scheduling(). Commands that don't require an adapter
> > reset will exit after processing, thus avoiding igc_tsn_offload_apply().
> > 
> > Fixes: d3750076d464 ("igc: Add TransmissionOverrun counter")
> > Signed-off-by: Faizal Rahim <faizal.abdul.rahim@linux.intel.com>
> > ---

Thank you for the patch. The code organization is much more logical this way.

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>