[dpdk-dev] [PATCH 01/17] vhost: introduce driver features related APIs

[Yuanhan Liu]

On Tue, Mar 14, 2017 at 10:53:23AM +0100, Maxime Coquelin wrote:
> 
> 
> On 03/14/2017 10:46 AM, Maxime Coquelin wrote:
> >
> >
> >On 03/03/2017 10:51 AM, Yuanhan Liu wrote:
> >>Introduce few APIs to set/get/enable/disable driver features.
> >>
> >>Signed-off-by: Yuanhan Liu <yuanhan.liu at linux.intel.com>
> >>---
> >> lib/librte_vhost/rte_vhost_version.map | 10 ++++
> >> lib/librte_vhost/rte_virtio_net.h      |  9 ++++
> >> lib/librte_vhost/socket.c              | 90
> >>++++++++++++++++++++++++++++++++++
> >> 3 files changed, 109 insertions(+)
> >
> >Nice!
> >Reviewed-by: Maxime Coquelin <maxime.coquelin at redhat.com>
> >
> >I wonder whether we could protect from setting/enabling/disabling
> >features once negotiation is done?

Those APIs won't be able to change the negotiated features. They are
just some interfaces before the vhost-user connection is established.

Ideally, we could/should get rid of the enabling/disabling functions:
let the vhost-user driver to handle the features directly (say, for
vhost-user pmd, we could use vdev options to disable/enable few specific
features). Once that is done, use the rte_vhost_driver_set_features()
set the features once.

The reason I introduced the enable/disable_features() is to keep the
compatability with the builtin vhost-user net driver (virtio_net.c).
If there is a plan to move it into vhost-pmd, they won't be needed.
And I don't think that will happen soon.

> Oh, I forgot one comment on this patch.
> Since these new functions are part to the API, shouldn't them be
> documented?

Yes, indeed, it's also noted in my cover letter.

	--yliu