Re: [dpdk-dev] [PATCH 7/7] vhost: simplify features set/get

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

On Thu, Aug 25, 2016 at 09:18:30AM +0200, Maxime Coquelin wrote:
> 
> 
> On 08/25/2016 05:03 AM, Yuanhan Liu wrote:
> >On Wed, Aug 24, 2016 at 10:11:57AM +0200, Maxime Coquelin wrote:
> >>
> >>
> >>On 08/18/2016 10:48 AM, Yuanhan Liu wrote:
> >>>No need to use a pointer to store/retrieve features.
> >>>
> >>>Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
> >>>---
> >>>lib/librte_vhost/vhost_user.c | 20 ++++++++------------
> >>>1 file changed, 8 insertions(+), 12 deletions(-)
> >>>
> >>>diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> >>>index ef4a0c1..eee99e9 100644
> >>>--- a/lib/librte_vhost/vhost_user.c
> >>>+++ b/lib/librte_vhost/vhost_user.c
> >>>@@ -155,23 +155,22 @@ vhost_user_reset_owner(struct virtio_net *dev)
> >>>/*
> >>> * The features that we support are requested.
> >>> */
> >>>-static int
> >>>-vhost_user_get_features(uint64_t *pu)
> >>>+static uint64_t
> >>>+vhost_user_get_features(void)
> >>>{
> >>>-	*pu = VHOST_FEATURES;
> >>>-	return 0;
> >>>+	return VHOST_FEATURES;
> >>>}
> >>
> >>This is not the topic of this series, but I wonder if it
> >>could make sense to be able to override supported features
> >>at device init time.
> >
> >Not quite sure I understood it correctly: is rte_vhost_feature_disable()
> >the answer you are looking for?
> Not really.
> 
> I meant a per-device supported features, and something you could set
> also via the vhost PMD options, without needing to recompile.

I see. I think my following proposal would fix it then.

    http://dpdk.org/ml/archives/dev/2016-June/040021.html

Note you might want to follow the discussion, as it mentioned
per-device config later.

Another note, it lacked a fancy name at last discussion. For
now, I think I come up with a better one: --dpdk-env :)

	--yliu

> 
> But maybe it would make more sense to do it a guest level?
> 
> Maxime