rte_eth_dev_socket_id return

[Danil Onishchenko]

Hello,

I faced a confusing behavior of rte_eth_dev_socket_id() function. In my 
application I configured eth port and if after that I call 
rte_eth_dev_socket_id(port) it returns -1. In documentation of the 
function it is said "Returns: The NUMA socket ID to which the Ethernet 
device is connected or a default of zero if the socket could not be 
determined. -1 is returned is the port_id value is out of range.". 
However if call rte_eth_dev_is_valid_port(port) with the same port id it 
returns 1. The documentation of this function says "Returns: 0 if port 
is out of range or not attached, 1 if device is attached". It looks like 
this functions can't return -1 and 1 respectively for the same port 
number. Are there any other cases when the first one can return -1?

Below is a code sample of port initialization and functions calls

static int port_init(uint16_t port, struct rte_mempool *mbuf_pool)
{
    struct rte_eth_conf port_conf;
    int i, retval = 0;
    struct rte_ether_addr ether_addr;
    struct rte_eth_dev_info dev_info;
        struct rte_eth_txconf txconf;
        const uint16_t rx_rings = 1, tx_rings = 1;
        uint16_t nb_rxd = RX_RING_SIZE, nb_txd = TX_RING_SIZE;
        char ethaddr[32];

    printf("ETH port found %u %.4x\n", (unsigned int)port, (unsigned 
int)port);

        memset(&port_conf, 0, sizeof(struct rte_eth_conf));

    if( !rte_eth_dev_is_valid_port(port) ) {
        printf("ETH port rte_eth_dev_is_valid_port(%.4x)==0\n", 
(unsigned int)port);
        return -1;
    }

    if( (retval = rte_eth_macaddr_get(port, &ether_addr)) != 0 ) {
        printf("ETH port rte_eth_macaddr_get(%.4x) != 0\n", (unsigned 
int)port);
        return retval;
    }

    printf("ETH port %.4x ethernet addr %s\n", (unsigned int)port, 
eth_addr_to_str(&ether_addr, ethaddr, 32));

    if( (retval = rte_eth_dev_info_get(port, &dev_info)) != 0 ) {
        printf("ETH port rte_eth_dev_info_get(%.4x) != 0\n", (unsigned 
int)port);
        return retval;
    }

    printf("Driver name: %s\n", dev_info.driver_name);

        if( dev_info.tx_offload_capa & RTE_ETH_TX_OFFLOAD_MBUF_FAST_FREE )
                port_conf.txmode.offloads |= 
RTE_ETH_TX_OFFLOAD_MBUF_FAST_FREE;

    if( (retval = rte_eth_dev_configure(port, rx_rings, tx_rings, 
&port_conf)) != 0 ) {
        printf("ETH port rte_eth_dev_configure(%.4x) != 0\n", (unsigned 
int)port);
                return retval;
    }

    if( (retval = rte_eth_dev_adjust_nb_rx_tx_desc(port, &nb_rxd, 
&nb_txd)) != 0 ) {
        printf("ETH port rte_eth_dev_adjust_nb_rx_tx_desc(%.4x) != 
0\n", (unsigned int)port);
        return retval;
    }

        /* Allocate and set up 1 RX queue per Ethernet port. */
        for( i = 0; i < rx_rings; ++i ) {
                if( (retval = rte_eth_rx_queue_setup(port, i, nb_rxd, 
rte_eth_dev_socket_id(port), NULL, mbuf_pool)) < 0 ) {
                    printf("ETH port rte_eth_rx_queue_setup(%.4x) < 
0\n", (unsigned int)port);
                        return retval;
        }
        }

        txconf = dev_info.default_txconf;
        txconf.offloads = port_conf.txmode.offloads;
        /* Allocate and set up 1 TX queue per Ethernet port. */
        for( i = 0; i < tx_rings; ++i ) {
                if( (retval = rte_eth_tx_queue_setup(port, i, nb_txd, 
rte_eth_dev_socket_id(port), &txconf)) < 0 ) {
                    printf("ETH port rte_eth_tx_queue_setup(%.4x) < 
0\n", (unsigned int)port);
                        return retval;
        }
        }

    if( (retval = rte_eth_dev_start(port)) < 0 ) {
        printf("ETH port rte_eth_dev_start(%.4x) < 0\n", (unsigned 
int)port);
        return retval;
    }

    if( (retval = rte_eth_macaddr_get(port, &ether_addr)) != 0 ) {
        printf("ETH port rte_eth_macaddr_get(%.4x) != 0\n", (unsigned 
int)port);
        goto cleanup;
    }

    printf("ETH port %.4x ethernet addr %s\n", (unsigned int)port, 
eth_addr_to_str(&ether_addr, ethaddr, 32));

        if( (retval = rte_eth_promiscuous_enable(port)) != 0 ) {
            printf("ETH port rte_eth_promiscuous_enable(%.4x) != 0\n", 
(unsigned int)port);
            goto cleanup;
    }

    printf("PORT %u rte_eth_dev_is_valid_port=%d 
rte_eth_dev_socket_id=%d\n", (unsigned int)port, 
rte_eth_dev_is_valid_port(port), rte_eth_dev_socket_id(port));

cleanup:
    if( retval != 0 )
        if( rte_eth_dev_stop(port) != 0 )
            printf("ETH port rte_eth_dev_stop(%.4x) != 0\n", (unsigned 
int)port);

finish:
    return retval;
}

The output of the line printf("PORT %u rte_eth_dev_is_valid_port=%d 
rte_eth_dev_socket_id=%d\n", (unsigned int)port, 
rte_eth_dev_is_valid_port(port), rte_eth_dev_socket_id(port));

PORT 0 rte_eth_dev_is_valid_port=1 rte_eth_dev_socket_id=-1

Btw during the start I can see a log message about NUMA if it might help

EAL: Detected NUMA nodes: 1