Hello All,
Specifics:
DPDK Version: dpdk-stable-18.11.11
Linux Kernel: 4.19.87
Intel 64-bit architecture
I am working on a code to support our socket based processes that need to run on
our DPDK-enabled platform. I am using the virtio_user exception path mechanism
to support this and initial tests seem fine.
However, I am seeing issues when we receive the packet from the virtio port,
that
the packet_type field is not set.
In my code, I have setup my physical PMD (i40e) as etherdev 0 and etherdev 1 and
have setup the virtual side with virtio as etherdev 2 and etherdev 3.
I am pairing this as etherdev 0 (physical) to etherdev 2 (virtio_user0) and
etherdev 1 (physical) to etherdev 3 (virtio_user1).
I am using the EAL function `rte_eal_hotplug_add()` as suggested in the
documentation.
I have added code in my dispatch function to generate a syslog(3) to print the
contents of the packet_type field in the received mbuf.
I then generate traffic to etherdev 1 from connected host and I am seeing the
following:
The inbound packet log shows -
Dec 7 21:24:45 2024 pmahan-dpdk pktdaemon-eal[27614]: CPU 2 TID
1140607382984128: [pktdaemon.NOTICE]: pkt_dpdk::switch_q_pkts()[2][1=>3][Q=0]:
mbuf packet type is 0x00000091
So etherdev 1 packet (physical) has packet_type of 0x91 which translates to
RTE_PTYPE_L2_ETHER
RTE_PTYPE_L3_IPV4_EXT_UNKNOWN
Which has been my experience for receiving packets from the physical PMD.
However, now that I have added the virtio port, the return packet does not seemed
to have this value set -
Dec 7 21:24:45 2024 pmahan-dpdk pktdaemon-eal[27614]: CPU 2 TID
1140607382984128: [pktdaemon.NOTICE]: pkt_dpdk::switch_q_pkts()[2][3=>1][Q=0]:
mbuf packet type is 0x00000000
I have looked into virtio PMD code and see that there is a function to fill in
the packet type called `virtio_rx_offload()` but it is only called if the
hardware associated with the virtual queue supports offloading and then only if
the `virtio_net_hdr` has no flags or its `gso_type` is not GSO_NONE.
If I ignore the flags and just inject the packets directly, everything seems to
work, but I have internal code that needs to know the basic ethernet type as well
as the L3 options and I was hoping to rely on the packet_type of the mbuf instead
of having to do packet groveling.
Is this an "as designed" or am I missing something in the configuration?
Thanks for any pointers,
Patrick
