[ovs-dev] [PATCH RFC] netdev-dpdk: Allow specification of index for PCI devices

[devendra rawat]

Hi Ciara,

On Fri, Oct 6, 2017 at 7:26 PM, Ciara Loftus <ciara.loftus at intel.com> wrote:

> Some NICs have only one PCI address associated with multiple ports. This
> patch extends the dpdk-devargs option's format to cater for such
> devices. Whereas before only one of N ports associated with one PCI
> address could be added, now N can.
>
> This patch allows for the following use of the dpdk-devargs option:
>
> ovs-vsctl set Interface myport options:dpdk-devargs=0000:06:00.0,X
>
> Where X is an unsigned integer representing one of multiple ports
> associated with the PCI address provided.
>
> This patch has not been tested.
>

I tested this patch on top of OVS v2.8.1 and DPDK v17.08. I used Mellanox
ConnectX-3 pro NIC for testing, this NIC provides two 10G ports
that share a single PCI address.

The patch is working fine, I was able to add both the 10G ports to OVS
bridge by specifying the port no. (0 or 1) in the dpdk-devargs.

# ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk
options:dpdk-devargs=0002:01:00.0,0
# ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk
options:dpdk-devargs=0002:01:00.0,1

the port no. (0 and 1) are bound to actual physical ports, i.e if I keep on
adding and deleting port no. 0 to bridge br0 multiple times,
every time I add the port back to br0, the same physical port is added to
bridge br0.

Thanks,
Devendra


>
> Signed-off-by: Ciara Loftus <ciara.loftus at intel.com>
> ---
>  lib/netdev-dpdk.c | 79 ++++++++++++++++++++++++++++++
> ++++++++++++++-----------
>  1 file changed, 63 insertions(+), 16 deletions(-)
>
> diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
> index c60f46f..c3562a3 100644
> --- a/lib/netdev-dpdk.c
> +++ b/lib/netdev-dpdk.c
> @@ -1214,30 +1214,77 @@ netdev_dpdk_lookup_by_port_id(dpdk_port_t port_id)
>  }
>
>  static dpdk_port_t
> +process_devargs_index(char *name, int idx)
> +{
> +    int i = 0;
> +    struct rte_eth_dev_info dev_info;
> +    char pci_addr[PCI_PRI_STR_SIZE];
> +    dpdk_port_t offset_port_id = DPDK_ETH_PORT_ID_INVALID;
> +
> +    for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
> +        if (!rte_eth_dev_is_valid_port(i)) {
> +            continue;
> +        }
> +        rte_eth_dev_info_get(i, &dev_info);
> +        rte_pci_device_name(&dev_info.pci_dev->addr, pci_addr,
> +                            sizeof(pci_addr));
> +        if (!strcmp(pci_addr, name)) {
> +            offset_port_id = i + idx;
> +            if (rte_eth_dev_is_valid_port(offset_port_id)) {
> +                rte_eth_dev_info_get(offset_port_id, &dev_info);
> +                rte_pci_device_name(&dev_info.pci_dev->addr, pci_addr,
> +                                    sizeof(pci_addr));
> +                if (!strcmp(pci_addr, name)) {
> +                    return offset_port_id;
> +                } else {
> +                    break;
> +                }
> +            } else {
> +                break;
> +            }
> +        }
> +    }
> +
> +    VLOG_INFO("Invalid PCI offset %i for device %s", idx, name);
> +    return DPDK_ETH_PORT_ID_INVALID;
> +}
> +
> +static dpdk_port_t
>  netdev_dpdk_process_devargs(struct netdev_dpdk *dev,
>                              const char *devargs, char **errp)
>  {
> -    /* Get the name up to the first comma. */
> -    char *name = xmemdup0(devargs, strcspn(devargs, ","));
> +    char *devargs_copy = xmemdup0((devargs), strlen(devargs));
> +    char *name, *idx_str;
> +    unsigned idx;
>      dpdk_port_t new_port_id = DPDK_ETH_PORT_ID_INVALID;
>
> -    if (!rte_eth_dev_count()
> -            || rte_eth_dev_get_port_by_name(name, &new_port_id)
> -            || !rte_eth_dev_is_valid_port(new_port_id)) {
> -        /* Device not found in DPDK, attempt to attach it */
> -        if (!rte_eth_dev_attach(devargs, &new_port_id)) {
> -            /* Attach successful */
> -            dev->attached = true;
> -            VLOG_INFO("Device '%s' attached to DPDK", devargs);
> -        } else {
> -            /* Attach unsuccessful */
> -            new_port_id = DPDK_ETH_PORT_ID_INVALID;
> -            VLOG_WARN_BUF(errp, "Error attaching device '%s' to DPDK",
> -                          devargs);
> +    name = strtok_r(devargs_copy, ",", &devargs_copy);
> +    idx_str = strtok_r(devargs_copy, ",", &devargs_copy);
> +
> +    if (idx_str) {
> +        idx = atoi(idx_str);
> +        new_port_id = process_devargs_index(name, idx);
> +    } else {
> +        if (!rte_eth_dev_count()
> +                || rte_eth_dev_get_port_by_name(name, &new_port_id)
> +                || !rte_eth_dev_is_valid_port(new_port_id)) {
> +            /* Device not found in DPDK, attempt to attach it */
> +            if (!rte_eth_dev_attach(devargs, &new_port_id)) {
> +                /* Attach successful */
> +                dev->attached = true;
> +                VLOG_INFO("Device '%s' attached to DPDK", devargs);
> +            } else {
> +                /* Attach unsuccessful */
> +                new_port_id = DPDK_ETH_PORT_ID_INVALID;
> +            }
>          }
>      }
>
> -    free(name);
> +    if (new_port_id == DPDK_ETH_PORT_ID_INVALID) {
> +        VLOG_WARN_BUF(errp, "Error attaching device '%s' to DPDK",
> +                      devargs);
> +    }
> +
>      return new_port_id;
>  }
>
> --
> 2.7.5
>
>