Re: DPDK mbuf pool in SR-IOV env and one RX/TX queue

On Mon, Jan 25, 2016 at 04:15:28PM -0800, Saurabh Mishra wrote:

Hi Bruce --

quoted

The sharing of the mbuf pool is not an issue, but sharing of rx/tx queues

is.

quoted

The ethdev queues are not multi-thread safe, so to share a queue between

processes

quoted

or threads, you need to put in locks or other access control mechanisms.

[This

quoted

also implies a performance hit due to the locking]
Regards,
/Bruce

Right. So now we have only one process to do rx/tx on queue 0 if we detect
that max queue support is 1.

However, we have noticed that if our process, which does rx/tx, is not
primary, then we can't transmit the packet out with SR-IOV.

Is there any specific limitation on SR-IOV (the vf driver in dpdk) that
only primary process should receive and transmit packets?

In our model, we have an agent process which monitor links and another
process which does packet processing. If we make our agent process as
primary then our secondary process is not able to send the packets --
rte_eth_tx_burst() succeed but recipient does not receive the packet.

Thanks,
/Saurabh

There should be no restrictions on RX/TX from secondary processes.

/Bruce