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From: Saurabh Mishra <saurabh.globe@gmail.com>
To: Bruce Richardson <bruce.richardson@intel.com>
Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] DPDK mbuf pool in SR-IOV env and one RX/TX queue
Date: Wed, 27 Jan 2016 20:39:26 -0800	[thread overview]
Message-ID: <CAMnwyJ2=ReheQ5R9h4GqnCx3cftNi8qY0J+O-tP2mXYWZF9KNA@mail.gmail.com> (raw)
In-Reply-To: <20160126201857.GB10276@bricha3-MOBL3>

Any clues or hint on how to debug this kind of problem on SR-IOV? Only
primary can send packet but secondary process couldn't. I have verified
host's qprc and qptc counters on PF and they do increment.

SR-IOV with DPDK seems more challenging than PCI pass through of whole NIC.

Saurabh
On Jan 26, 2016 12:19 PM, "Bruce Richardson" <bruce.richardson@intel.com>
wrote:

> On Mon, Jan 25, 2016 at 04:15:28PM -0800, Saurabh Mishra wrote:
> > Hi Bruce --
> >
> > >The sharing of the mbuf pool is not an issue, but sharing of rx/tx
> queues
> > is.
> > >The ethdev queues are not multi-thread safe, so to share a queue between
> > processes
> > >or threads, you need to put in locks or other access control mechanisms.
> > [This
> > >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
>

      reply	other threads:[~2016-01-28  4:39 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-22  4:35 Saurabh Mishra
2016-01-23 16:09 ` Bruce Richardson
2016-01-26  0:15   ` Saurabh Mishra
2016-01-26 20:18     ` Bruce Richardson
2016-01-28  4:39       ` Saurabh Mishra [this message]

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