mir/ovs
2
0
Fork 0
mirror of https://github.com/openvswitch/ovs synced 2025-08-29 13:27:59 +00:00
Code Issues Releases Wiki Activity

dpdk: Deprecate vhost-user dequeue zero-copy.

Browse Source 
Dequeue zero-copy is no longer supported for vhost-user client mode
in DPDK due to commit [1].

In addition to this, zero-copy mode has been proposed to be marked
deprecated in [2] with removal in the next DPDK LTS release.

This commit deprecates support for vhost-user dequeue zero-copy in OVS
with its removal expected in the next OVS release.

[1] 715070ea10e6 ("vhost: prevent zero-copy with incompatible client
    mode")
[2] http://mails.dpdk.org/archives/dev/2020-August/177236.html

Signed-off-by: Ian Stokes <ian.stokes@intel.com>
Acked-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Ilya Maximets <i.maximets@ovn.org>
This commit is contained in:
Ian Stokes 2020-08-06 16:28:35 +01:00
parent 71417ef011
commit e919fd4955
3 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
Documentation/topics/dpdk/vhost-user.rst
View File

@ -556,6 +556,11 @@ shown with::
vhost-user Dequeue Zero Copy (experimental) vhost-user Dequeue Zero Copy (experimental)
------------------------------------------- -------------------------------------------
.. warning::
vhost-user Dequeue Zero Copy is deprecated in OVS and will be removed in
the next release.
Normally when dequeuing a packet from a vHost User device, a memcpy operation Normally when dequeuing a packet from a vHost User device, a memcpy operation
must be used to copy that packet from guest address space to host address must be used to copy that packet from guest address space to host address
space. This memcpy can be removed by enabling dequeue zero-copy like so:: space. This memcpy can be removed by enabling dequeue zero-copy like so::

2
NEWS
View File

@ -22,6 +22,8 @@ v2.14.0 - xx xxx xxxx
CVE-2020-10726, this DPDK version is strongly recommended to be used. CVE-2020-10726, this DPDK version is strongly recommended to be used.
* New 'ovs-appctl dpdk/log-list' and 'ovs-appctl dpdk/log-set' commands * New 'ovs-appctl dpdk/log-list' and 'ovs-appctl dpdk/log-set' commands
to list and change log levels in DPDK components. to list and change log levels in DPDK components.
* Vhost-user Dequeue zero-copy support is deprecated and will be removed
in the next release.
- Linux datapath: - Linux datapath:
* Support for kernel versions up to 5.5.x. * Support for kernel versions up to 5.5.x.
- AF_XDP: - AF_XDP:

2
lib/netdev-dpdk.c
View File

@ -5085,6 +5085,8 @@ netdev_dpdk_vhost_client_reconfigure(struct netdev *netdev)
dev->up.name, dev->vhost_id); dev->up.name, dev->vhost_id);
if (zc_enabled) { if (zc_enabled) {
VLOG_INFO("Zero copy enabled for vHost port %s", dev->up.name); VLOG_INFO("Zero copy enabled for vHost port %s", dev->up.name);
VLOG_WARN("Zero copy support is deprecated and will be "
"removed in the next OVS release.");
} }
} }