> -----Original Message-----
> From: dev <dev-boun...@dpdk.org> On Behalf Of Stephen Hemminger
> Sent: Friday 3 September 2021 17:15
> To: dev@dpdk.org
> Cc: Stephen Hemminger <step...@networkplumber.org>;
> sta...@dpdk.org; xiaolong...@intel.com
> Subject: [dpdk-dev] [PATCH] net/af_xdp: fix support of secondary process
>
> Doing basic operations like info_get or get_stats was broken
> in af_xdp PMD. The info_get would crash because dev->device
> was NULL in secondary process. Fix this by doing same initialization
> as af_packet and tap devices.
>
> The get_stats would crash because the XDP socket is not open in
> primary process. As a workaround don't query kernel for dropped
> packets when called from secondary process.
>
> Note: this does not address the other bug which is that transmitting
> in secondary process is broken because the send() in tx_kick
> will fail because XDP socket fd is not valid in secondary process.
Hi Stephen,
Apologies for the delayed reply, I was on vacation.
In the Bugzilla report you suggest we:
"mark AF_XDP as broken in with primary/secondary
and return an error in probe in secondary process".
I agree with this suggestion. However with this patch we still permit
secondary, and just make sure it doesn't crash for get_stats. Did you change
your mind?
Personally, I would prefer to have primary/secondary either working 100% or
else not allowed at all by throwing an error during probe. What do you think?
Do you have a reason/use case to permit secondary processes despite some
features not being available eg. full stats, tx?
Thanks,
Ciara
>
> Bugzilla ID: 805
> Fixes: f1debd77efaf ("net/af_xdp: introduce AF_XDP PMD")
> Cc: sta...@dpdk.org
> Cc: xiaolong...@intel.com
> Ciara Loftus <ciara.lof...@intel.com>
> Qi Zhang <qi.z.zh...@intel.com>
> Anatoly Burakov <anatoly.bura...@intel.com>
>
> Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
> ---
> drivers/net/af_xdp/rte_eth_af_xdp.c | 17 +++++++++--------
> 1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c
> b/drivers/net/af_xdp/rte_eth_af_xdp.c
> index 74ffa4511284..70abc14fa753 100644
> --- a/drivers/net/af_xdp/rte_eth_af_xdp.c
> +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
> @@ -860,7 +860,7 @@ eth_stats_get(struct rte_eth_dev *dev, struct
> rte_eth_stats *stats)
> struct pkt_rx_queue *rxq;
> struct pkt_tx_queue *txq;
> socklen_t optlen;
> - int i, ret;
> + int i;
>
> for (i = 0; i < dev->data->nb_rx_queues; i++) {
> optlen = sizeof(struct xdp_statistics);
> @@ -876,13 +876,12 @@ eth_stats_get(struct rte_eth_dev *dev, struct
> rte_eth_stats *stats)
> stats->ibytes += stats->q_ibytes[i];
> stats->imissed += rxq->stats.rx_dropped;
> stats->oerrors += txq->stats.tx_dropped;
> - ret = getsockopt(xsk_socket__fd(rxq->xsk), SOL_XDP,
> - XDP_STATISTICS, &xdp_stats, &optlen);
> - if (ret != 0) {
> - AF_XDP_LOG(ERR, "getsockopt() failed for
> XDP_STATISTICS.\n");
> - return -1;
> - }
> - stats->imissed += xdp_stats.rx_dropped;
> +
> + /* The socket fd is not valid in secondary process */
> + if (rte_eal_process_type() != RTE_PROC_SECONDARY &&
> + getsockopt(xsk_socket__fd(rxq->xsk), SOL_XDP,
> + XDP_STATISTICS, &xdp_stats, &optlen) == 0)
> + stats->imissed += xdp_stats.rx_dropped;
>
> stats->opackets += stats->q_opackets[i];
> stats->obytes += stats->q_obytes[i];
> @@ -1799,7 +1798,9 @@ rte_pmd_af_xdp_probe(struct rte_vdev_device
> *dev)
> AF_XDP_LOG(ERR, "Failed to probe %s\n", name);
> return -EINVAL;
> }
> + /* TODO: reconnect socket from primary */
> eth_dev->dev_ops = &ops;
> + eth_dev->device = &dev->device;
> rte_eth_dev_probing_finish(eth_dev);
> return 0;
> }
> --
> 2.30.2