Re: [dpdk-dev] [PATCH] event/rx_adapter: fix ignore return of event start

["Rao, Nikhil" <nikhil.rao@intel.com>]

Adding eventdev PMD folks for their suggestions on how to handle the return value from rte_event_dev_start() below.

> -----Original Message-----
> From: Varghese, Vipin
> Sent: Wednesday, January 31, 2018 4:26 AM
> To: dev@dpdk.org; Rao, Nikhil <nikhil.rao@intel.com>
> Cc: Jain, Deepak K <deepak.k.jain@intel.com>; Varghese, Vipin
> <vipin.varghese@intel.com>
> Subject: [PATCH] event/rx_adapter: fix ignore return of event start
> 
> Capture the return value for rte_event_dev_start. Return the result back to
> user.
> 
> Coverity issue: 257000
> Fixes: 9c38b704d280 ("eventdev: add eth Rx adapter implementation")
> Cc: nikhil.rao@intel.com
> 
> Signed-off-by: Vipin Varghese <vipin.varghese@intel.com>
> ---
>  lib/librte_eventdev/rte_event_eth_rx_adapter.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> b/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> index 90106e6..a818bef 100644
> --- a/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> +++ b/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> @@ -603,7 +603,7 @@ static uint16_t gcd_u16(uint16_t a, uint16_t b)
>  		RTE_EDEV_LOG_ERR("failed to configure event dev %u\n",
>  						dev_id);
>  		if (started)
> -			rte_event_dev_start(dev_id);
> +			ret = rte_event_dev_start(dev_id);

Currently the a non-zero return value at this point signifies an error returned from rte_event_dev_configure(),  so I suggest that the return value is typecasted to void.

>  		return ret;
>  	}
> 
> @@ -617,7 +617,7 @@ static uint16_t gcd_u16(uint16_t a, uint16_t b)
>  	conf->event_port_id = port_id;
>  	conf->max_nb_rx = 128;
>  	if (started)
> -		rte_event_dev_start(dev_id);
> +		ret = rte_event_dev_start(dev_id);
This change looks good to me.

>  	rx_adapter->default_cb_arg = 1;
>  	return ret;
>  }
> --
> 1.9.1