[ovs-dev] [PATCH] dpdk: announce deprecation of vhost-user server ports

[Mooney, Sean K]

> -----Original Message-----
> From: Aaron Conole [mailto:aconole at redhat.com]
> Sent: Thursday, June 8, 2017 8:12 PM
> To: Kevin Traynor <ktraynor at redhat.com>
> Cc: dev at openvswitch.org; Darrell Ball <dball at vmware.com>; Loftus, Ciara
> <ciara.loftus at intel.com>; Mooney, Sean K <sean.k.mooney at intel.com>
> Subject: Re: [PATCH] dpdk: announce deprecation of vhost-user server
> ports
> 
> Hi Kevin,
> 
> Kevin Traynor <ktraynor at redhat.com> writes:
> 
> > On 06/07/2017 11:46 PM, Aaron Conole wrote:
> >> Since vhost-user server mode ports are the preferred mechanism for
> >> interconnecting Open vSwitch with VMs when using DPDK, and since
> >> there are currently no known use cases for vhost-user server mode
> >> ports apart from version incompatibilities with QEMU, announce that
> >> server mode ports are considered deprecated and will be removed in a
> future release.

[Mooney, Sean K] not to be pedantic but you contradicted your self her. First sentence
You say vhost-user server mode ports are preferred then you say lets remove them.
I would suggest you use the interface names instead and say dpdkvhostuser when referring to what will be removed
Server mode port is ambigious since its not clear if you are referring to qemu or dpdk when you say server mode.

> >>
> >> Cc: Ciara Loftus <ciara.loftus at intel.com>
> >> Cc: Kevin Traynor <ktraynor at redhat.com>
> >> Suggested-by: Darrell Ball <dball at vmware.com>
> >> Signed-off-by: Aaron Conole <aconole at redhat.com>
> >> ---
> >>  Documentation/topics/dpdk/vhost-user.rst | 24 ++++++++++++++++-----
> ---
> >>  NEWS                                     |  2 ++
> >>  lib/netdev-dpdk.c                        |  2 ++
> >>  3 files changed, 20 insertions(+), 8 deletions(-)
> >>
> >> diff --git a/Documentation/topics/dpdk/vhost-user.rst
> >> b/Documentation/topics/dpdk/vhost-user.rst
> >> index a1c19fd..9d36cf2 100644
> >> --- a/Documentation/topics/dpdk/vhost-user.rst
> >> +++ b/Documentation/topics/dpdk/vhost-user.rst
> >> @@ -32,13 +32,19 @@ documentation`_ on same.
> >>  Quick Example
> >>  -------------
> >>
> >> -This example demonstrates how to add two ``dpdkvhostuser`` ports to
> >> an existing -bridge called ``br0``::
> >> +This example demonstrates how to add two ``dpdkvhostuserclient``
> >> +ports to an existing bridge called ``br0``::
> >>
> >> -    $ ovs-vsctl add-port br0 dpdkvhostuser0 \
> >> -        -- set Interface dpdkvhostuser0 type=dpdkvhostuser
> >> -    $ ovs-vsctl add-port br0 dpdkvhostuser1 \
> >> -        -- set Interface dpdkvhostuser1 type=dpdkvhostuser
> >> +    $ ovs-vsctl add-port br0 dpdkvhostclient0 \
> >> +        -- set Interface dpdkvhostclient0 type=dpdkvhostuserclient
> \
> >> +           options:vhost-server-path=/tmp/dpdkvhostclient0
> >> +    $ ovs-vsctl add-port br0 dpdkvhostclient1 \
> >> +        -- set Interface dpdkvhostclient1 type=dpdkvhostuserclient
> \
> >> +           options:vhost-server-path=/tmp/dpdkvhostclient1
> >> +
> >> +For the above examples to work, an appropriate server socket must
> be
> >> +created at the paths specified (``/tmp/dpdkvhostclient0`` and
> >> +``/tmp/dpdkvhostclient0``).
> >
> > You could mention QEMU here. So the reader knows where to look.
> > "These can be created by QEMU. See below for details."?
> 
> Good idea.  I'll add it.
> 
> Thanks for the review!
> 
> >>  vhost-user vs. vhost-user-client
> >>  --------------------------------
> >> @@ -59,7 +65,8 @@ means if OVS dies, all VMs **must** be restarted.
> >> On the other hand, for  vhost-user-client ports, OVS acts as the
> >> client and QEMU the server. This means  OVS can die and be restarted
> >> without issue, and it is also possible to restart  an instance
> >> itself. For this reason, vhost-user-client ports are the preferred -
> type for most use cases.
> >> +type for most use cases.  Ports of type vhost-user are currently
> >> +deprecated and will be removed in a future release.
> >>
> >>  .. _dpdk-vhost-user:
> >>
> >> @@ -68,7 +75,8 @@ vhost-user
> >>
> >>  .. important::
> >>
> >> -   Use of vhost-user ports requires QEMU >= 2.2
> >> +   Use of vhost-user ports requires QEMU >= 2.2;  vhost-user ports
> are
> >> +   *deprecated*.
> >>
> >>  To use vhost-user ports, you must first add said ports to the
> >> switch. DPDK  vhost-user ports can have arbitrary names with the
> >> exception of forward and diff --git a/NEWS b/NEWS index
> >> 82004c8..b81d033 100644
> >> --- a/NEWS
> >> +++ b/NEWS
> >> @@ -16,6 +16,8 @@ Post-v2.7.0
> >>         Log level can be changed in a usual OVS way using
> >>         'ovs-appctl vlog' commands for 'dpdk' module. Lower bound
> >>         still can be configured via extra arguments for DPDK EAL.
> >> +     * dpdkvhostuser ports are marked as deprecated.  They will be
> removed
> >> +       in an upcoming release.
> >>     - IPFIX now provides additional counters:
> >>       * Total counters since metering process startup.
> >>       * Per-flow TCP flag counters.
> >> diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c index
> >> b770b70..9ab4aeb 100644
> >> --- a/lib/netdev-dpdk.c
> >> +++ b/lib/netdev-dpdk.c
> >> @@ -966,6 +966,8 @@ netdev_dpdk_vhost_construct(struct netdev
> *netdev)
> >>      err = vhost_common_construct(netdev);
> >>
> >>      ovs_mutex_unlock(&dpdk_mutex);
> >> +    VLOG_WARN_ONCE("dpdkvhostuser ports are considered deprecated;
> "
> >> +                   "please migrate to dpdkvhostuserclient ports.");
> >>      return err;
> >>  }
> >>
> >>