From: Stephen Hemminger <stephen@networkplumber.org>
To: changchun.ouyang@intel.com
Cc: dev@dpdk.org, Stephen Hemminger <shemming@brocade.com>
Subject: [dpdk-dev] [PATCH 5/5] virtio: fix ring size negotiation
Date: Thu, 11 Jun 2015 08:53:27 -0700 [thread overview]
Message-ID: <1434038007-8964-6-git-send-email-stephen@networkplumber.org> (raw)
In-Reply-To: <1434038007-8964-1-git-send-email-stephen@networkplumber.org>
From: Stephen Hemminger <shemming@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@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
next prev parent reply other threads:[~2015-06-11 15:53 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-11 15:53 [dpdk-dev] [PATCH 0/5 v3] virtio: patches Stephen Hemminger
2015-06-11 15:53 ` [dpdk-dev] [PATCH 1/5] virtio: remove blank lines Stephen Hemminger
2015-06-12 1:28 ` Ouyang, Changchun
2015-06-11 15:53 ` [dpdk-dev] [PATCH 2/5] virtio: don't enable/disable rx modes unless supported Stephen Hemminger
2015-06-12 1:29 ` Ouyang, Changchun
2015-06-11 15:53 ` [dpdk-dev] [PATCH 3/5] virtio: don't set mac table unless negotiated Stephen Hemminger
2015-06-12 1:30 ` Ouyang, Changchun
2015-06-11 15:53 ` [dpdk-dev] [PATCH 4/5] virtio: clarify feature bit handling Stephen Hemminger
2015-06-12 1:36 ` Ouyang, Changchun
2015-06-11 15:53 ` Stephen Hemminger [this message]
2015-06-12 1:49 ` [dpdk-dev] [PATCH 5/5] virtio: fix ring size negotiation Ouyang, Changchun
2015-06-12 12:46 ` [dpdk-dev] [PATCH 0/5 v3] virtio: patches Thomas Monjalon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1434038007-8964-6-git-send-email-stephen@networkplumber.org \
--to=stephen@networkplumber.org \
--cc=changchun.ouyang@intel.com \
--cc=dev@dpdk.org \
--cc=shemming@brocade.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).