Re: [dpdk-dev] [PATCH] ethdev: report error on name truncation

[Andrew Rybchenko <arybchenko@solarflare.com>]

On 1/7/19 5:40 PM, Nithin Kumar Dabilpuram wrote:
> Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>
> ---
>   lib/librte_ethdev/rte_ethdev.c | 12 ++++++++++--
>   1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
> index 9d5107d..bd45445 100644
> --- a/lib/librte_ethdev/rte_ethdev.c
> +++ b/lib/librte_ethdev/rte_ethdev.c
> @@ -3588,9 +3588,17 @@ rte_eth_dma_zone_reserve(const struct rte_eth_dev *dev, const char *ring_name,
>   {
>   	char z_name[RTE_MEMZONE_NAMESIZE];
>   	const struct rte_memzone *mz;
> +	int rc;
>   
> -	snprintf(z_name, sizeof(z_name), "eth_p%d_q%d_%s",
> -		 dev->data->port_id, queue_id, ring_name);
> +	rc = snprintf(z_name, sizeof(z_name), "%s_%s_%d_%d",
> +		      dev->device->driver->name, ring_name,
> +		      dev->data->port_id, queue_id);
> +
> +	if (rc >= RTE_MEMZONE_NAMESIZE) {
> +		RTE_LOG(ERR, EAL, "%s(): truncated name\n", __func__);
> +		rte_errno = ENAMETOOLONG;
> +		return NULL;
> +	}
>   
>   	mz = rte_memzone_lookup(z_name);
>   	if (mz)

It is good to report an error in the case of name truncation, but the patch
does more. It changes format of the memzone name, adds the driver name
in it (what is bad since testpmd has commands to find the memzone by name
and read descriptors (hack, but sometimes very useful)).
Also I'm not sure about function name in the log message. Other places
do not have it.