Re: [PATCH 1/1] net/mlx5: add dynamic logging for mlx5_dump_err_cqe

[Aru <aru.kolappan@oracle.com>]

Hi Leon,

Thank you for reviewing the patch.

The method you mentioned disables the dump permanently for the kernel.
We thought vendor might have enabled it for their consumption when needed.
Hence we made it dynamic, so that it can be enabled/disabled at run time.

Especially, in a production environment, having the option to turn this 
log on/off
at runtime will be helpful.

Feel free to share your thoughts.

Thanks,
Aru

On 10/13/22 3:43 AM, Leon Romanovsky wrote:
> On Wed, Oct 12, 2022 at 04:52:52PM -0700, Aru Kolappan wrote:
>> From: Arumugam Kolappan <aru.kolappan@oracle.com>
>>
>> Presently, mlx5 driver dumps error CQE by default for few syndromes. Some
>> syndromes are expected due to application behavior[Ex: REMOTE_ACCESS_ERR
>> for revoking rkey before RDMA operation is completed]. There is no option
>> to disable the log if the application decided to do so. This patch
>> converts the log into dynamic print and by default, this debug print is
>> disabled. Users can enable/disable this logging at runtime if needed.
>>
>> Suggested-by: Manjunath Patil <manjunath.b.patil@oracle.com>
>> Signed-off-by: Arumugam Kolappan <aru.kolappan@oracle.com>
>> ---
>>   drivers/infiniband/hw/mlx5/cq.c | 2 +-
>>   include/linux/mlx5/cq.h         | 4 ++--
>>   2 files changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/infiniband/hw/mlx5/cq.c b/drivers/infiniband/hw/mlx5/cq.c
>> index be189e0..890cdc3 100644
>> --- a/drivers/infiniband/hw/mlx5/cq.c
>> +++ b/drivers/infiniband/hw/mlx5/cq.c
>> @@ -269,7 +269,7 @@ static void handle_responder(struct ib_wc *wc, struct mlx5_cqe64 *cqe,
>>   
>>   static void dump_cqe(struct mlx5_ib_dev *dev, struct mlx5_err_cqe *cqe)
>>   {
>> -	mlx5_ib_warn(dev, "dump error cqe\n");
>> +	mlx5_ib_dbg(dev, "dump error cqe\n");
> This path should be handled in switch<->case of mlx5_handle_error_cqe()
> by skipping dump_cqe for MLX5_CQE_SYNDROME_REMOTE_ACCESS_ERR.
>
> diff --git a/drivers/infiniband/hw/mlx5/cq.c b/drivers/infiniband/hw/mlx5/cq.c
> index be189e0525de..2d75c3071a1e 100644
> --- a/drivers/infiniband/hw/mlx5/cq.c
> +++ b/drivers/infiniband/hw/mlx5/cq.c
> @@ -306,6 +306,7 @@ static void mlx5_handle_error_cqe(struct mlx5_ib_dev *dev,
>                  wc->status = IB_WC_REM_INV_REQ_ERR;
>                  break;
>          case MLX5_CQE_SYNDROME_REMOTE_ACCESS_ERR:
> +               dump = 0;
>                  wc->status = IB_WC_REM_ACCESS_ERR;
>                  break;
>          case MLX5_CQE_SYNDROME_REMOTE_OP_ERR:
>
> Thanks