From: Stephen Hemminger <shemm...@brocade.com>
Negotate the virtio ring size. The host may allow for very large
rings but application may only want a smaller ring.
Conversely, if the number of descriptors requested exceeds the virtio
host queue size, then just silently use the smaller host size.
This fixes issues with virtio in non-QEMU envirionments.
For example Google Compute Engine allows up to 16K elements
in ring.
Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
drivers/net/virtio/virtio_ethdev.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/drivers/net/virtio/virtio_ethdev.c
b/drivers/net/virtio/virtio_ethdev.c
index 2afa371..befd0bc 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -267,13 +267,21 @@ int virtio_dev_queue_setup(struct rte_eth_dev *dev,
if (vq_size == 0) {
PMD_INIT_LOG(ERR, "%s: virtqueue does not exist", __func__);
return -EINVAL;
- } else if (!rte_is_power_of_2(vq_size)) {
+ }
+
+ if (!rte_is_power_of_2(vq_size)) {
PMD_INIT_LOG(ERR, "%s: virtqueue size is not powerof 2",
__func__);
return -EINVAL;
- } else if (nb_desc != vq_size) {
- PMD_INIT_LOG(ERR, "Warning: nb_desc(%d) is not equal to vq size
(%d), fall to vq size",
- nb_desc, vq_size);
- nb_desc = vq_size;
+ }
+
+ if (nb_desc < vq_size) {
+ if (!rte_is_power_of_2(nb_desc)) {
+ PMD_INIT_LOG(ERR,
+ "nb_desc(%u) size is not powerof 2",
+ nb_desc);
+ return -EINVAL;
+ }
+ vq_size = nb_desc;
}
if (queue_type == VTNET_RQ) {
--
2.1.4
