On 04/05/2018 12:10 PM, Jens Freimann wrote:
Implement enqueue of packets to the receive virtqueue.
Set descriptor flag VIRTQ_DESC_F_USED and toggle used wrap counter if
last descriptor in ring is used. Perform a write memory barrier before
flags are written to descriptor.
Chained descriptors are not supported with this patch.
Signed-off-by: Jens Freimann <jfreim...@redhat.com>
---
lib/librte_vhost/virtio_net.c | 129 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 129 insertions(+)
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 7eea1da04..578e5612e 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -695,6 +695,135 @@ virtio_dev_merge_rx(struct virtio_net *dev, uint16_t
queue_id,
return pkt_idx;
}
+static inline uint32_t __attribute__((always_inline))
+vhost_enqueue_burst_packed(struct virtio_net *dev, uint16_t queue_id,
+ struct rte_mbuf **pkts, uint32_t count)
+{
+ struct vhost_virtqueue *vq;
+ struct vring_desc_packed *descs;
+ uint16_t idx;
+ uint16_t mask;
+ uint16_t i;
+
+ vq = dev->virtqueue[queue_id];
+
+ rte_spinlock_lock(&vq->access_lock);
+
+ if (unlikely(vq->enabled == 0)) {
+ i = 0;
+ goto out_access_unlock;
+ }
+
+ if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
+ vhost_user_iotlb_rd_lock(vq);
+
+ descs = vq->desc_packed;
+ mask = vq->size - 1;
+
+ for (i = 0; i < count; i++) {
+ uint32_t desc_avail, desc_offset;
+ uint32_t mbuf_avail, mbuf_offset;
+ uint32_t cpy_len;
+ struct vring_desc_packed *desc;
+ uint64_t desc_addr;
+ struct virtio_net_hdr_mrg_rxbuf *hdr;
+ struct rte_mbuf *m = pkts[i];
+
+ /* XXX: there is an assumption that no desc will be chained */
Is this assumption still true?
If not what are the plan to fix this?
+ idx = vq->last_used_idx & mask;
+ desc = &descs[idx];
+
+ if (!desc_is_avail(vq, desc))
IIUC, it means the ring is full.
I think this is an unlikely case, so maybe better to use the unlikely
macro here.
+ break;
+ rte_smp_rmb();
+
+ desc_addr = vhost_iova_to_vva(dev, vq, desc->addr,
+ sizeof(*desc), VHOST_ACCESS_RW);
+ /*
+ * Checking of 'desc_addr' placed outside of 'unlikely' macro
+ * to avoid performance issue with some versions of gcc (4.8.4
+ * and 5.3.0) which otherwise stores offset on the stack instead
+ * of in a register.
+ */
+ if (unlikely(desc->len < dev->vhost_hlen) || !desc_addr)
+ break;
+
+ hdr = (struct virtio_net_hdr_mrg_rxbuf *)(uintptr_t)desc_addr;
+ virtio_enqueue_offload(m, &hdr->hdr);
+ vhost_log_write(dev, desc->addr, dev->vhost_hlen);
+ PRINT_PACKET(dev, (uintptr_t)desc_addr, dev->vhost_hlen, 0);
+
+ desc_offset = dev->vhost_hlen;
+ desc_avail = desc->len - dev->vhost_hlen;
+
+ mbuf_avail = rte_pktmbuf_data_len(m);
+ mbuf_offset = 0;
+ while (mbuf_avail != 0 || m->next != NULL) {
+ /* done with current mbuf, fetch next */
+ if (mbuf_avail == 0) {
+ m = m->next;
+
+ mbuf_offset = 0;
+ mbuf_avail = rte_pktmbuf_data_len(m);
+ }
+
+ /* done with current desc buf, fetch next */
+ if (desc_avail == 0) {
+ if ((desc->flags & VRING_DESC_F_NEXT) == 0) {
+ /* Room in vring buffer is not enough */
+ goto out;
+ }
+
+ idx = (idx+1) & (vq->size - 1);
+ desc = &descs[idx];
+ if (unlikely(!desc_is_avail(vq, desc)))
+ goto out ;
+
+ desc_addr = vhost_iova_to_vva(dev, vq,
desc->addr,
+ sizeof(*desc),
+ VHOST_ACCESS_RW);
+ if (unlikely(!desc_addr))
+ goto out;
+
+ desc_offset = 0;
+ desc_avail = desc->len;
+ }
+
+ cpy_len = RTE_MIN(desc_avail, mbuf_avail);
+ rte_memcpy((void *)((uintptr_t)(desc_addr +
desc_offset)),
+ rte_pktmbuf_mtod_offset(m, void *, mbuf_offset),
+ cpy_len);
+ vhost_log_write(dev, desc->addr + desc_offset, cpy_len);
+ PRINT_PACKET(dev, (uintptr_t)(desc_addr + desc_offset),
+ cpy_len, 0);
+
+ mbuf_avail -= cpy_len;
+ mbuf_offset += cpy_len;
+ desc_avail -= cpy_len;
+ desc_offset += cpy_len;
+ }
+
+ descs[idx].len = pkts[i]->pkt_len + dev->vhost_hlen;
+ rte_smp_wmb();
+ set_desc_used(vq, desc);
+
+ vq->last_used_idx++;
+ if ((vq->last_used_idx & (vq->size - 1)) == 0)
+ toggle_wrap_counter(vq);
+ }
+
+out:
+ if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
+ vhost_user_iotlb_rd_unlock(vq);
+
+out_access_unlock:
+ rte_spinlock_unlock(&vq->access_lock);
+
+ count = i;
+
+ return count;
+}
+
uint16_t
rte_vhost_enqueue_burst(int vid, uint16_t queue_id,
struct rte_mbuf **pkts, uint16_t count)
