Re: [dpdk-dev] [PATCH 0/2] net/virtio: support to turn on/off the traffic flow

["Yang, Zhiyong" <zhiyong.yang@intel.com>]

Hi, yuanhan:
	Sorry for the delay reply due to my annual leave.

> -----Original Message-----
> From: Yuanhan Liu [mailto:yuanhan.liu@linux.intel.com]
> Sent: Thursday, April 6, 2017 12:00 PM
> To: Yang, Zhiyong <zhiyong.yang@intel.com>
> Cc: dev@dpdk.org; maxime.coquelin@redhat.com
> Subject: Re: [PATCH 0/2] net/virtio: support to turn on/off the traffic flow
> 
> On Fri, Mar 31, 2017 at 07:40:17PM +0800, Zhiyong Yang wrote:
> > Current dpdk code virtio_dev_stop only disables interrupt and marks
> > link down, When it is invoked, tx/rx traffic flows still work. This is a strange
> behavior.
> > The patchset supports the switch of flow by calling virtio_dev_start/stop.
> >
> > The implementation refers to vhost pmd.
> 
> That's a difference story. Vhost pmd uses 2 vars to track the status, whereas you
> are using only one here. So why not setting/clearing "started" at dev_start/stop,
> respectively?
> Then we can check "started" at Rx/Tx functions.

Yes, I use only one var since I think vhost pmd using two is too complex and it is unnecessary.
I'm setting/clearing started at virtio_dev_start/stop,  update_queuing_status is added to avoid
duplicate code. I don't understand your question.

> 
> BTW, why does it have to be atomic?
> 

Consider again. It is not necessary to use atomic here. But It seems that it doesn't  have an negative effect.

Thanks
Zhiyong

> 	--yliu
> >
> > Zhiyong Yang (2):
> >   net/virtio: add data elements to turn on/off traffic flow
> >   net/virtio: support to turn on/off the traffic flow
> >
> >  drivers/net/virtio/virtio_ethdev.c           | 37 +++++++++++++++++++++++++++-
> >  drivers/net/virtio/virtio_pci.h              |  1 +
> >  drivers/net/virtio/virtio_rxtx.c             | 12 +++++++++
> >  drivers/net/virtio/virtio_rxtx.h             |  6 +++++
> >  drivers/net/virtio/virtio_rxtx_simple.c      |  4 +++
> >  drivers/net/virtio/virtio_rxtx_simple_neon.c |  5 +++-
> > drivers/net/virtio/virtio_rxtx_simple_sse.c  |  5 +++-
> >  drivers/net/virtio/virtio_user_ethdev.c      |  1 +
> >  8 files changed, 68 insertions(+), 3 deletions(-)
> >
> > --
> > 2.7.4