Re: [PATCH net-next v5] net: ti: icssg_prueth: add TAPRIO offload support

[MD Danish Anwar <danishanwar@ti.com>]

Hi Paolo,

On 02/05/24 5:29 pm, Paolo Abeni wrote:
> On Mon, 2024-04-29 at 16:00 +0530, MD Danish Anwar wrote:
>> +static int emac_taprio_replace(struct net_device *ndev,
>> +			       struct tc_taprio_qopt_offload *taprio)
>> +{
>> +	struct prueth_emac *emac = netdev_priv(ndev);
>> +	struct tc_taprio_qopt_offload *est_new;
>> +	int ret;
>> +
>> +	if (taprio->cycle_time_extension) {
>> +		NL_SET_ERR_MSG_MOD(taprio->extack, "Cycle time extension not supported");
>> +		return -EOPNOTSUPP;
>> +	}
>> +
>> +	if (taprio->cycle_time < TAS_MIN_CYCLE_TIME) {
>> +		NL_SET_ERR_MSG_FMT_MOD(taprio->extack, "cycle_time %llu is less than min supported cycle_time %d",
>> +				       taprio->cycle_time, TAS_MIN_CYCLE_TIME);
>> +		return -EINVAL;
>> +	}
>> +
>> +	if (taprio->num_entries > TAS_MAX_CMD_LISTS) {
>> +		NL_SET_ERR_MSG_FMT_MOD(taprio->extack, "num_entries %lu is more than max supported entries %d",
>> +				       taprio->num_entries, TAS_MAX_CMD_LISTS);
>> +		return -EINVAL;
>> +	}
>> +
>> +	if (emac->qos.tas.taprio_admin)
>> +		devm_kfree(&ndev->dev, emac->qos.tas.taprio_admin);
> 
> it looks like 'qos.tas.taprio_admin' is initialized from
> taprio_offload_get(), so it should be free with taprio_offload_free(),
> right?
> 

'qos.tas.taprio_admin' is assigned by "emac->qos.tas.taprio_admin =
taprio_offload_get(taprio);". Here I will free it with taprio_offload_free()

>> +
>> +	est_new = devm_kzalloc(&ndev->dev,
>> +			       struct_size(est_new, entries, taprio->num_entries),
>> +			       GFP_KERNEL);
>> +	if (!est_new)
>> +		return -ENOMEM;
> 
> Why are you allocating 'est_new'? it looks like it's not used
> anywhere?!? 
> 

Sorry my bad. Forgot to remove est_new. I will remove it.

>> +
>> +	emac->qos.tas.taprio_admin = taprio_offload_get(taprio);
>> +	ret = tas_update_oper_list(emac);
>> +	if (ret)
>> +		return ret;
> 
> Should the above clear 'taprio_admin' on error, as well? 
> 

Yes here also we should clear taprio_admin and taprio on error. I will
add a goto label and clear taprio on both errors.

Below is the diff to address handling of taprio and taprio_admin.

diff --git a/drivers/net/ethernet/ti/icssg/icssg_qos.c
b/drivers/net/ethernet/ti/icssg/icssg_qos.c
index 459463ea6c20..c7cadab0edec 100644
--- a/drivers/net/ethernet/ti/icssg/icssg_qos.c
+++ b/drivers/net/ethernet/ti/icssg/icssg_qos.c
@@ -210,7 +210,7 @@ static int emac_taprio_replace(struct net_device *ndev,
 	}

 	if (emac->qos.tas.taprio_admin)
-		devm_kfree(&ndev->dev, emac->qos.tas.taprio_admin);
+		taprio_offload_free(emac->qos.tas.taprio_admin);

 	est_new = devm_kzalloc(&ndev->dev,
 			       struct_size(est_new, entries, taprio->num_entries),
@@ -221,13 +221,15 @@ static int emac_taprio_replace(struct net_device
*ndev,
 	emac->qos.tas.taprio_admin = taprio_offload_get(taprio);
 	ret = tas_update_oper_list(emac);
 	if (ret)
-		return ret;
+		goto clear_taprio;

 	ret = tas_set_state(emac, TAS_STATE_ENABLE);
-	if (ret) {
-		emac->qos.tas.taprio_admin = NULL;
-		taprio_offload_free(taprio);
-	}
+	if (ret)
+		goto clear_taprio;
+
+clear_taprio:
+	emac->qos.tas.taprio_admin = NULL;
+	taprio_offload_free(taprio);

 	return ret;
 }

Please have a look and let me know if this looks ok to you.


>>
> Thanks,
> 
> Paolo
> 

-- 
Thanks and Regards,
Danish