Re: [dpdk-dev] [DPDK] net/virtio: packed ring notification data feature support

["Jiang, Cheng1" <cheng1.jiang@intel.com>]

> -----Original Message-----
> From: Liu, Yong
> Sent: Monday, December 9, 2019 10:00 AM
> To: Jiang, Cheng1 <cheng1.jiang@intel.com>; dev@dpdk.org
> Cc: maxime.coquelin@redhat.com; Bie, Tiwei <tiwei.bie@intel.com>; Wang,
> Zhihong <zhihong.wang@intel.com>; Jiang, Cheng1
> <cheng1.jiang@intel.com>
> Subject: RE: [dpdk-dev] [DPDK] net/virtio: packed ring notification data
> feature support
> 
> 
> 
> > -----Original Message-----
> > From: dev <dev-bounces@dpdk.org> On Behalf Of Cheng Jiang
> > Sent: Wednesday, December 04, 2019 11:03 PM
> > To: dev@dpdk.org
> > Cc: maxime.coquelin@redhat.com; Bie, Tiwei <tiwei.bie@intel.com>;
> > Wang, Zhihong <zhihong.wang@intel.com>; Jiang, Cheng1
> > <cheng1.jiang@intel.com>
> > Subject: [dpdk-dev] [DPDK] net/virtio: packed ring notification data
> > feature support
> >
> > This patch supports the feature that the driver passes extra data
> > (besides identifying the virtqueue) in its device notifications.
> >
> > Signed-off-by: Cheng Jiang <Cheng1.jiang@intel.com>
> > ---
> >  drivers/net/virtio/virtio_ethdev.h |  3 ++-
> >  drivers/net/virtio/virtio_pci.c    | 15 ++++++++++++++-
> >  drivers/net/virtio/virtio_pci.h    |  6 ++++++
> >  3 files changed, 22 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/virtio/virtio_ethdev.h
> > b/drivers/net/virtio/virtio_ethdev.h
> > index a10111758..cd8947656 100644
> > --- a/drivers/net/virtio/virtio_ethdev.h
> > +++ b/drivers/net/virtio/virtio_ethdev.h
> > @@ -36,7 +36,8 @@
> >  	 1ULL << VIRTIO_F_IN_ORDER        |	\
> >  	 1ULL << VIRTIO_F_RING_PACKED	  |	\
> >  	 1ULL << VIRTIO_F_IOMMU_PLATFORM  |	\
> > -	 1ULL << VIRTIO_F_ORDER_PLATFORM)
> > +	 1ULL << VIRTIO_F_ORDER_PLATFORM  |	\
> > +	 1ULL << VIRTIO_F_NOTIFICATION_DATA)
> >
> >  #define VIRTIO_PMD_SUPPORTED_GUEST_FEATURES	\
> >  	(VIRTIO_PMD_DEFAULT_GUEST_FEATURES |	\
> > diff --git a/drivers/net/virtio/virtio_pci.c
> > b/drivers/net/virtio/virtio_pci.c index 4468e89cb..2462a7dab 100644
> > --- a/drivers/net/virtio/virtio_pci.c
> > +++ b/drivers/net/virtio/virtio_pci.c
> > @@ -418,7 +418,20 @@ modern_del_queue(struct virtio_hw *hw, struct
> > virtqueue *vq)  static void  modern_notify_queue(struct virtio_hw *hw
> > __rte_unused, struct virtqueue
> > *vq)
> >  {
> 
> Hi Cheng,
> hw pointer will be used in notify function, please remove rte_unused
> attribute.
> 
> Thanks,
> Marvin
> 

Sure, I'll remove it in the next version.

Thanks very much!
Cheng

> > -	rte_write16(vq->vq_queue_index, vq->notify_addr);
> > +	uint32_t notify_data;
> > +
> > +	if (!vtpci_with_feature(hw, VIRTIO_F_NOTIFICATION_DATA)) {
> > +		rte_write16(vq->vq_queue_index, vq->notify_addr);
> > +		return;
> > +	}
> > +
> > +	if (vtpci_with_feature(hw, VIRTIO_F_RING_PACKED))
> > +		notify_data = ((((uint32_t)vq-
> >vq_packed.used_wrap_counter <<
> > 15) |
> > +				vq->vq_avail_idx) << 16) | vq-
> >vq_queue_index;
> > +	else
> > +		notify_data = ((uint32_t)vq->vq_avail_idx << 16) |
> > +				vq->vq_queue_index;
> > +	rte_write32(notify_data, vq->notify_addr);
> >  }
> >
> >  const struct virtio_pci_ops modern_ops = { diff --git
> > a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
> > index a38cb45ad..7433d2f08 100644
> > --- a/drivers/net/virtio/virtio_pci.h
> > +++ b/drivers/net/virtio/virtio_pci.h
> > @@ -135,6 +135,12 @@ struct virtnet_ctl;
> >   */
> >  #define VIRTIO_F_ORDER_PLATFORM 36
> >
> > +/*
> > + * This feature indicates that the driver passes extra data (besides
> > + * identifying the virtqueue) in its device notifications.
> > + */
> > +#define VIRTIO_F_NOTIFICATION_DATA 38
> > +
> >  /* The Guest publishes the used index for which it expects an interrupt
> >   * at the end of the avail ring. Host should ignore the avail->flags
> > field. */
> >  /* The Host publishes the avail index for which it expects a kick
> > --
> > 2.17.1