Thanks, Ferruh I will perform the suggested recommendations in version 3 of the patch.
On Mon, 20 Sept 2021 at 18:41, Ferruh Yigit <ferruh.yi...@intel.com> wrote: > On 9/8/2021 9:59 AM, Tudor Cornea wrote: > > The af_packet pmd driver binds to a raw socket and allows > > sending and receiving of packets through the kernel. > > > > Since commit [1], the kernel strips the vlan tags early in > > __netif_receive_skb_core(), so we receive untagged packets while > > running with the af_packet pmd. > > > > Luckily for us, the skb vlan-related fields are still populated from the > > stripped vlan tags, so we end up having all the information > > that we need in the mbuf. > > > > Having the PMD driver support DEV_RX_OFFLOAD_VLAN_STRIP allows the > > application to control the desired vlan stripping behavior. > > > > [1] > https://github.com/torvalds/linux/commit/bcc6d47903612c3861201cc3a866fb604f26b8b2 > > > > Signed-off-by: Tudor Cornea <tudor.cor...@gmail.com> > > > > Hi Tudor, > > The concern was unexpected performance degradation (user not setting any > offload > will have performance drop). But since your measurements show no > significant > drop, I think it is fair to make driver behave same as other drivers. > (Until we have a way to describe offloads that can't be disabled by PMDs.) > > Can you do a few minor updates: > - Put your performance measurements into to the commit log to record them > - Update the af_packet documentation (doc/guides/nics/af_packet.rst) to > document > PMD behavior with packets with VLAN tag > - Update release note (doc/guides/rel_notes/release_21_11.rst) with a > one/two > sentences to document the change, to notify possible users of the > af_packet with > the change. > > Thanks, > ferruh > > > --- > > v2: > > * Add DEV_RX_OFFLOAD_VLAN_STRIP to rxmode->offloads > > --- > > drivers/net/af_packet/rte_eth_af_packet.c | 12 ++++++++++++ > > 1 file changed, 12 insertions(+) > > > > diff --git a/drivers/net/af_packet/rte_eth_af_packet.c > b/drivers/net/af_packet/rte_eth_af_packet.c > > index b73b211..5ed9dd6 100644 > > --- a/drivers/net/af_packet/rte_eth_af_packet.c > > +++ b/drivers/net/af_packet/rte_eth_af_packet.c > > @@ -48,6 +48,7 @@ struct pkt_rx_queue { > > > > struct rte_mempool *mb_pool; > > uint16_t in_port; > > + uint8_t vlan_strip; > > > > volatile unsigned long rx_pkts; > > volatile unsigned long rx_bytes; > > @@ -78,6 +79,7 @@ struct pmd_internals { > > > > struct pkt_rx_queue *rx_queue; > > struct pkt_tx_queue *tx_queue; > > + uint8_t vlan_strip; > > }; > > > > static const char *valid_arguments[] = { > > @@ -148,6 +150,9 @@ eth_af_packet_rx(void *queue, struct rte_mbuf > **bufs, uint16_t nb_pkts) > > if (ppd->tp_status & TP_STATUS_VLAN_VALID) { > > mbuf->vlan_tci = ppd->tp_vlan_tci; > > mbuf->ol_flags |= (PKT_RX_VLAN | > PKT_RX_VLAN_STRIPPED); > > + > > + if (!pkt_q->vlan_strip && rte_vlan_insert(&mbuf)) > > + PMD_LOG(ERR, "Failed to reinsert VLAN > tag"); > > } > > > > /* release incoming frame and advance ring buffer */ > > @@ -302,6 +307,11 @@ eth_dev_stop(struct rte_eth_dev *dev) > > static int > > eth_dev_configure(struct rte_eth_dev *dev __rte_unused) > > { > > + struct rte_eth_conf *dev_conf = &dev->data->dev_conf; > > + const struct rte_eth_rxmode *rxmode = &dev_conf->rxmode; > > + struct pmd_internals *internals = dev->data->dev_private; > > + > > + internals->vlan_strip = !!(rxmode->offloads & > DEV_RX_OFFLOAD_VLAN_STRIP); > > return 0; > > } > > > > @@ -318,6 +328,7 @@ eth_dev_info(struct rte_eth_dev *dev, struct > rte_eth_dev_info *dev_info) > > dev_info->min_rx_bufsize = 0; > > dev_info->tx_offload_capa = DEV_TX_OFFLOAD_MULTI_SEGS | > > DEV_TX_OFFLOAD_VLAN_INSERT; > > + dev_info->rx_offload_capa = DEV_RX_OFFLOAD_VLAN_STRIP; > > > > return 0; > > } > > @@ -448,6 +459,7 @@ eth_rx_queue_setup(struct rte_eth_dev *dev, > > > > dev->data->rx_queues[rx_queue_id] = pkt_q; > > pkt_q->in_port = dev->data->port_id; > > + pkt_q->vlan_strip = internals->vlan_strip; > > > > return 0; > > } > > > >
