On Tue, Mar 21, 2023 at 11:32:36PM -0400, Michael S. Tsirkin wrote: > On Tue, Mar 21, 2023 at 01:28:08PM +0200, Eli Cohen wrote: > > Following patch adds driver support for VIRTIO_NET_F_MRG_RXBUF. > > > > Current firmware versions show degradation in packet rate when using > > MRG_RXBUF. Users who favor memory saving over packet rate could enable > > this feature but we want to keep it off by default. > > > > One can still enable it when creating the vdpa device using vdpa tool by > > providing features that include it. > > > > For example: > > $ vdpa dev add name vdpa0 mgmtdev pci/0000:86:00.2 device_features > > 0x300cb982b > > > > > > Acked-by: Jason Wang <[email protected]> > > Signed-off-by: Eli Cohen <[email protected]> > > > I have a question. Could you guys try with the recent XDP mergeable > buffer rework? Does this address the performance issue you are > observing? > > Specifically: > > Message-Id: <[email protected]> > Message-Id: <[email protected]> > > I would very much appreciate if you posted perf numbers > in response to that thread - both to help evaluate that > patchset and this one. > Thanks!
Oh sorry, I got confused. That is still preparatory work not real zero copy. The patchset to try is this: Message-Id: <[email protected]> > > --- > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c > > b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > index 520646ae7fa0..502c482a93ce 100644 > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > @@ -3122,6 +3122,8 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev > > *v_mdev, const char *name, > > return -EINVAL; > > } > > device_features &= add_config->device_features; > > + } else { > > + device_features &= ~BIT_ULL(VIRTIO_NET_F_MRG_RXBUF); > > } > > if (!(device_features & BIT_ULL(VIRTIO_F_VERSION_1) && > > device_features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM))) { > > -- > > 2.38.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
