On Wed, May 12, 2021 at 5:30 AM Wang, Yinan <yinan.w...@intel.com> wrote: > > Hi David, > > Since vhost tx offload can’t work now, we report a Bugzilla as below, could > you help to take a look? > https://bugs.dpdk.org/show_bug.cgi?id=702
(I discovered your mail from 05/08 only today, now that I got a new mail, might be a pebcak from me, sorry...) - Looking at the bz, there is a first issue/misconception. testpmd only does TSO or any kind of tx offloading with the csum forward engine. The iofwd engine won't make TSO possible. - Let's say we use the csum fwd engine, testpmd configures drivers through the ethdev API. The ethdev API states that no offloading is enabled unless requested by the application. TSO, l3/l4 checksums offloading are documented as: https://doc.dpdk.org/guides/nics/features.html#l3-checksum-offload https://doc.dpdk.org/guides/nics/features.html#lro But the vhost pmd does not report such capabilities. https://git.dpdk.org/dpdk/tree/drivers/net/vhost/rte_eth_vhost.c#n1276 So we can't expect testpmd to have tso working with net/vhost pmd. - The csum offloading engine swaps mac addresses. I would expect issues with inter vm traffic. In summary, I think this is a bad test. If it worked with the commands in the bugzilla before my change (which I doubt), it was wrong. > We also tried vhost example with VM2VM iperf test, large pkts also can't > forwarding. "large pkts", can you give details? I tried to use this example, without/with my change, but: When I try to start this example with a physical port and two vhosts, I get a crash (division by 0 on vdmq stuff). When I start it without a physical port, I get a complaint about no port being enabled. Passing a portmask 0x1 seems to work, the example starts but, next, no traffic is forwarded (not even arp). Hooking gdb, I never get packet dequeued from vhost. -- David Marchand
