Re: [dpdk-dev] [PATCH] examples/tep_term: fix return value check

["Li, Xiaoyun" <xiaoyun.li@intel.com>]

Hi

> -----Original Message-----
> From: Ye, Xiaolong
> Sent: Monday, February 10, 2020 11:37
> To: Li, Xiaoyun <xiaoyun.li@intel.com>
> Cc: Kovacevic, Marko <marko.kovacevic@intel.com>; dev@dpdk.org;
> stable@dpdk.org
> Subject: Re: [PATCH] examples/tep_term: fix return value check
> 
> On 02/10, Xiaoyun Li wrote:
> >Added return value check for 'rte_eth_dev_info_get()'.
> >
> >Coverity issue: 349922
> >Fixes: 2bb43bd4350a ("examples/tep_term: add TSO offload configuration")
> >Cc: stable@dpdk.org
> >
> >Signed-off-by: Xiaoyun Li <xiaoyun.li@intel.com>
> >---
> > examples/tep_termination/vxlan_setup.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> >diff --git a/examples/tep_termination/vxlan_setup.c
> b/examples/tep_termination/vxlan_setup.c
> >index eca119a72..bd469f5f4 100644
> >--- a/examples/tep_termination/vxlan_setup.c
> >+++ b/examples/tep_termination/vxlan_setup.c
> >@@ -195,7 +195,9 @@ vxlan_port_init(uint16_t port, struct rte_mempool
> *mbuf_pool)
> >
> > 	if (tso_segsz != 0) {
> > 		struct rte_eth_dev_info dev_info;
> >-		rte_eth_dev_info_get(port, &dev_info);
> >+		retval = rte_eth_dev_info_get(port, &dev_info);
> >+		if (retval != 0)
> >+			return -retval;
> 
> why return -retval not retval?

The description of return value of rte_eth_dev_info_get() is like the following:
@return
 *   - (0) if successful.
 *   - (-ENOTSUP) if support for dev_infos_get() does not exist for the device.
 *   - (-ENODEV) if *port_id* invalid.
So -retval is the real err code.
But the check of this function (vxlan_port_init) is (overlay_options.port_configure(portid, mbuf_pool) != 0)
So return -retval or retval are both OK.
> 
> Thanks,
> Xiaolong
> 
> > 		if ((dev_info.tx_offload_capa & DEV_TX_OFFLOAD_TCP_TSO)
> == 0)
> > 			RTE_LOG(WARNING, PORT,
> > 				"hardware TSO offload is not supported\n");
> >--
> >2.17.1
> >