Re: [PATCH mlx5-next 01/10] net/mlx5: Rework handling of port module events

[Jason Gunthorpe <jgg@mellanox.com>]

On Sun, Dec 09, 2018 at 07:04:33PM -0800, Saeed Mahameed wrote:
> From: Mikhael Goikhman <migo@mellanox.com>
> 
> Add explicit HW defined error values. For simplicity, keep counters for all
> statuses starting from 0, although currently status=0 is not used.
> 
> Additionally, when HW signals an unexpected cable status, it is reported
> now rather than ignored. And status counter is now updated on errors.
> 
> Signed-off-by: Mikhael Goikhman <migo@mellanox.com>
> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
>  .../ethernet/mellanox/mlx5/core/en_stats.c    |  8 +-
>  .../net/ethernet/mellanox/mlx5/core/events.c  | 83 ++++++++++++-------
>  .../ethernet/mellanox/mlx5/core/lib/mlx5.h    | 19 ++---
>  3 files changed, 65 insertions(+), 45 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
> index 748d23806391..881c54c12e19 100644
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.c
> @@ -1087,13 +1087,13 @@ static void mlx5e_grp_per_prio_update_stats(struct mlx5e_priv *priv)
>  }
>  
>  static const struct counter_desc mlx5e_pme_status_desc[] = {
> -	{ "module_unplug", 8 },
> +	{ "module_unplug",       sizeof(u64) * MLX5_MODULE_STATUS_UNPLUGGED },
>  };
>  
>  static const struct counter_desc mlx5e_pme_error_desc[] = {
> -	{ "module_bus_stuck", 16 },       /* bus stuck (I2C or data shorted) */
> -	{ "module_high_temp", 48 },       /* high temperature */
> -	{ "module_bad_shorted", 56 },    /* bad or shorted cable/module */
> +	{ "module_bus_stuck",    sizeof(u64) * MLX5_MODULE_EVENT_ERROR_BUS_STUCK },
> +	{ "module_high_temp",    sizeof(u64) * MLX5_MODULE_EVENT_ERROR_HIGH_TEMPERATURE },
> +	{ "module_bad_shorted",  sizeof(u64) * MLX5_MODULE_EVENT_ERROR_BAD_CABLE },
>  };
>  
>  #define NUM_PME_STATUS_STATS		ARRAY_SIZE(mlx5e_pme_status_desc)
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/events.c b/drivers/net/ethernet/mellanox/mlx5/core/events.c
> index e92df7020a26..587d93ec905f 100644
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/events.c
> @@ -157,23 +157,43 @@ static int temp_warn(struct notifier_block *nb, unsigned long type, void *data)
>  }
>  
>  /* MLX5_EVENT_TYPE_PORT_MODULE_EVENT */
> -static const char *mlx5_pme_status[MLX5_MODULE_STATUS_NUM] = {
> -	"Cable plugged",   /* MLX5_MODULE_STATUS_PLUGGED    = 0x1 */
> -	"Cable unplugged", /* MLX5_MODULE_STATUS_UNPLUGGED  = 0x2 */
> -	"Cable error",     /* MLX5_MODULE_STATUS_ERROR      = 0x3 */
> -};
> +static const char *mlx5_pme_status_to_string(enum port_module_event_status_type status)
> +{
> +	switch (status) {
> +	case MLX5_MODULE_STATUS_PLUGGED:
> +		return "Cable plugged";
> +	case MLX5_MODULE_STATUS_UNPLUGGED:
> +		return "Cable unplugged";
> +	case MLX5_MODULE_STATUS_ERROR:
> +		return "Cable error";
> +	default:
> +		return "Unknown status";
> +	}
> +}

Arrays are usually a bette codegen bet than switch/case unless the array is
very sparse, but it should be written as

  [MLX5_MODULE_STATUS_PLUGGED] = "Cable plugged",

Commit message should explain why this is being converted. Maybe it is
very sparse?

Jason