Re: [PATCH net-next 02/12] net/mlx5: LAG, Refactor lag logic

[Alexander Lobakin <aleksander.lobakin@intel.com>]

From: Rongwei Liu <rongweil@nvidia.com>
Date: Tue, 17 Dec 2024 13:44:07 +0800

> 
> 
> On 2024/12/17 01:55, Alexander Lobakin wrote:
>> From: Tariq Toukan <tariqt@nvidia.com>
>> Date: Wed, 11 Dec 2024 15:42:13 +0200
>>
>>> From: Rongwei Liu <rongweil@nvidia.com>
>>>
>>> Wrap the lag pf access into two new macros:
>>> 1. ldev_for_each()
>>> 2. ldev_for_each_reverse()
>>> The maximum number of lag ports and the index to `natvie_port_num`
>>> mapping will be handled by the two new macros.
>>> Users shouldn't use the for loop anymore.
>>
>> [...]
>>
>>> @@ -1417,6 +1398,26 @@ void mlx5_lag_add_netdev(struct mlx5_core_dev *dev,
>>>  	mlx5_queue_bond_work(ldev, 0);
>>>  }
>>>  
>>> +int get_pre_ldev_func(struct mlx5_lag *ldev, int start_idx, int end_idx)
>>> +{
>>> +	int i;
>>> +
>>> +	for (i = start_idx; i >= end_idx; i--)
>>> +		if (ldev->pf[i].dev)
>>> +			return i;
>>> +	return -1;
>>> +}
>>> +
>>> +int get_next_ldev_func(struct mlx5_lag *ldev, int start_idx)
>>> +{
>>> +	int i;
>>> +
>>> +	for (i = start_idx; i < MLX5_MAX_PORTS; i++)
>>> +		if (ldev->pf[i].dev)
>>> +			return i;
>>> +	return MLX5_MAX_PORTS;
>>> +}
>>
>> Why aren't these two prefixed with mlx5?
>> We can have. No mlx5 prefix aligns with "ldev_for_each/ldev_for_each_reverse()", simple, short and meaningful.

All drivers must have its symbols prefixed, otherwise there might be
name conflicts at anytime and also it's not clear where a definition
comes from if it's not prefixed.

>>> +
>>>  bool mlx5_lag_is_roce(struct mlx5_core_dev *dev)
>>>  {
>>>  	struct mlx5_lag *ldev;
>>
>> [...]
>>
>>>  
>>> +#define ldev_for_each(i, start_index, ldev) \
>>> +	for (int tmp = start_index; tmp = get_next_ldev_func(ldev, tmp), \
>>> +	     i = tmp, tmp < MLX5_MAX_PORTS; tmp++)
>>> +
>>> +#define ldev_for_each_reverse(i, start_index, end_index, ldev)      \
>>> +	for (int tmp = start_index, tmp1 = end_index; \
>>> +	     tmp = get_pre_ldev_func(ldev, tmp, tmp1), \
>>> +	     i = tmp, tmp >= tmp1; tmp--)
>>
>> Same?
> Reverse is used to the error handling. Add end index is more convenient.
> Of course, we can remove the end_index. 
> But all the logic need to add:
> 	if (i < end_index)
> 		break;
> If no strong comments, I would like to keep as now.

By "same?" I meant that there two are also not prefixed with mlx5_, the
same as the two above.

Thanks,
Olek