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

[Mor Bar-Gabay <morx.bar.gabay@intel.com>]

On 25/06/2024 11:26, 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>
> Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> ---
>   drivers/net/ethernet/intel/igc/igc_main.c | 33 ++++++++++++-----------
>   1 file changed, 17 insertions(+), 16 deletions(-)
> 
Tested-by: Mor Bar-Gabay <morx.bar.gabay@intel.com>