Re: [dpdk-dev] [PATCH v3 04/21] net/virtio: add packed virtqueue helpers

[Jens Freimann <jfreimann@redhat.com>]

On Thu, Apr 05, 2018 at 04:27:51PM +0200, Maxime Coquelin wrote:
>
>On 04/05/2018 12:10 PM, Jens Freimann wrote:
>>Add helper functions to set/clear and check descriptor flags.
>>
>>Signed-off-by: Jens Freimann <jfreimann@redhat.com>
>>---
>>  drivers/net/virtio/virtio_ring.h | 33 +++++++++++++++++++++++++++++++++
>>  drivers/net/virtio/virtqueue.c   | 10 ++++++++++
>>  2 files changed, 43 insertions(+)
>>
>>diff --git a/drivers/net/virtio/virtio_ring.h b/drivers/net/virtio/virtio_ring.h
>>index 54a11d2a9..663b4b01d 100644
>>--- a/drivers/net/virtio/virtio_ring.h
>>+++ b/drivers/net/virtio/virtio_ring.h
>>@@ -78,6 +78,7 @@ struct vring_packed_desc_event {
>>  struct vring {
>>  	unsigned int num;
>>+	unsigned int avail_wrap_counter;
>>  	union {
>>  		struct vring_desc_packed *desc_packed;
>>  		struct vring_desc *desc;
>>@@ -92,6 +93,38 @@ struct vring {
>>  	};
>>  };
>>+static inline void toggle_wrap_counter(struct vring *vr)
>Please follow the coding style of the driver:
>
>static inline void
>toggle_wrap_counter(struct vring *vr)
>
>I would also prefix the functions with vring_ to keep consistency.

ok

>>+{
>>+	vr->avail_wrap_counter ^= 1;
>>+}
>>+
>>+static inline void _set_desc_avail(struct vring_desc_packed *desc,
>>+				   int wrap_counter)
>>+{
>>+	uint16_t flags = desc->flags;
>>+
>>+	if (wrap_counter) {
>>+		flags |= VRING_DESC_F_AVAIL;
>>+		flags &= ~VRING_DESC_F_USED;
>>+	} else {
>>+		flags &= ~VRING_DESC_F_AVAIL;
>>+		flags |= VRING_DESC_F_USED;
>>+	}
>>+
>>+	desc->flags = flags;
>>+}
>>+
>>+static inline void set_desc_avail(struct vring *vr,
>>+				  struct vring_desc_packed *desc)
>>+{
>>+	_set_desc_avail(desc, vr->avail_wrap_counter);
>>+}
>>+
>>+static inline int desc_is_used(struct vring_desc_packed *desc)
>>+{
>>+	return !(desc->flags & VRING_DESC_F_AVAIL) == !(desc->flags & VRING_DESC_F_USED);
>>+}
>>+
>>  /* The standard layout for the ring is a continuous chunk of memory which
>>   * looks like this.  We assume num is a power of 2.
>>   *
>>diff --git a/drivers/net/virtio/virtqueue.c b/drivers/net/virtio/virtqueue.c
>>index a7d0a9cbe..4f95ed5c8 100644
>>--- a/drivers/net/virtio/virtqueue.c
>>+++ b/drivers/net/virtio/virtqueue.c
>>@@ -58,6 +58,7 @@ virtqueue_detach_unused(struct virtqueue *vq)
>>  void
>>  virtqueue_rxvq_flush(struct virtqueue *vq)
>>  {
>>+	struct vring_desc_packed *descs = vq->vq_ring.desc_packed;
>>  	struct virtnet_rx *rxq = &vq->rxq;
>>  	struct virtio_hw *hw = vq->hw;
>>  	struct vring_used_elem *uep;
>>@@ -65,6 +66,15 @@ virtqueue_rxvq_flush(struct virtqueue *vq)
>>  	uint16_t used_idx, desc_idx;
>>  	uint16_t nb_used, i;
>>+	if (vtpci_packed_queue(vq->hw)) {
>>+		i = vq->vq_used_cons_idx & (vq->vq_nentries - 1);
>>+		while (desc_is_used(&descs[i])) {
>>+			rte_pktmbuf_free(vq->sw_ring[i]);
>>+			vq->vq_free_cnt++;
>>+		}
>>+		return;
>>+	}
>>+
>>  	nb_used = VIRTQUEUE_NUSED(vq);
>>  	for (i = 0; i < nb_used; i++) {
>>
>
>With style comments taken into account:

I'll fix it.

Thanks!
regards,
Jens 
>
>Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>