From: Jason Wang <jasowang@redhat.com>
To: rusty@rustcorp.com.au, mst@redhat.com,
virtualization@lists.linux-foundation.org,
linux-kernel@vger.kernel.org
Cc: Jason Wang <jasowang@redhat.com>
Subject: [RFC PATCH 3/3] virtio-net: using single MSIX irq for each TX/RX queue pair
Date: Fri, 26 Dec 2014 10:53:45 +0800 [thread overview]
Message-ID: <1419562425-20614-4-git-send-email-jasowang@redhat.com> (raw)
In-Reply-To: <1419562425-20614-1-git-send-email-jasowang@redhat.com>
This patch try to reduce the number of MSIX irqs required for
virtio-net by sharing a MSIX irq for each TX/RX queue pair through
channels. If transport support channel, about half of the MSIX irqs
were reduced.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/net/virtio_net.c | 26 +++++++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 3ba3499..03a0c28 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -72,6 +72,9 @@ struct send_queue {
/* Name of the send queue: output.$index */
char name[40];
+
+ /* Name of the channel, share with rxq */
+ char channel_name[40];
};
/* Internal representation of a receive virtqueue */
@@ -1522,6 +1525,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
int ret = -ENOMEM;
int i, total_vqs;
const char **names;
+ const char **channel_names;
+ unsigned *channels;
/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
* possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
@@ -1540,6 +1545,14 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
if (!names)
goto err_names;
+ channel_names = kmalloc_array(vi->max_queue_pairs,
+ sizeof(*channel_names),
+ GFP_KERNEL);
+ if (!channel_names)
+ goto err_channel_names;
+ channels = kmalloc_array(total_vqs, sizeof(*channels), GFP_KERNEL);
+ if (!channels)
+ goto err_channels;
/* Parameters for control virtqueue, if any */
if (vi->has_cvq) {
@@ -1555,10 +1568,15 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
sprintf(vi->sq[i].name, "output.%d", i);
names[rxq2vq(i)] = vi->rq[i].name;
names[txq2vq(i)] = vi->sq[i].name;
+ sprintf(vi->sq[i].channel_name, "txrx.%d", i);
+ channel_names[i] = vi->sq[i].channel_name;
+ channels[rxq2vq(i)] = i;
+ channels[txq2vq(i)] = i;
}
ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
- names, NULL, NULL, 0);
+ names, channels, channel_names,
+ vi->max_queue_pairs);
if (ret)
goto err_find;
@@ -1573,6 +1591,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
vi->sq[i].vq = vqs[txq2vq(i)];
}
+ kfree(channels);
+ kfree(channel_names);
kfree(names);
kfree(callbacks);
kfree(vqs);
@@ -1580,6 +1600,10 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
return 0;
err_find:
+ kfree(channels);
+err_channels:
+ kfree(channel_names);
+err_channel_names:
kfree(names);
err_names:
kfree(callbacks);
--
1.8.3.1
next prev parent reply other threads:[~2014-12-26 2:54 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-26 2:53 [RFC PATCH 0/3] Sharing MSIX irq for tx/rx queue pairs Jason Wang
2014-12-26 2:53 ` [RFC PATCH 1/3] virtio-pci: introduce channels Jason Wang
2014-12-26 2:53 ` [RFC PATCH 2/3] virtio: let vp_find_vqs accept channel setting paramters Jason Wang
2014-12-26 2:53 ` Jason Wang [this message]
2014-12-26 10:17 ` [RFC PATCH 3/3] virtio-net: using single MSIX irq for each TX/RX queue pair Jason Wang
2014-12-28 7:52 ` [RFC PATCH 0/3] Sharing MSIX irq for tx/rx queue pairs Michael S. Tsirkin
2015-01-04 8:38 ` Jason Wang
2015-01-04 11:36 ` Michael S. Tsirkin
2015-01-05 3:09 ` Jason Wang
2015-01-05 1:39 ` Rusty Russell
2015-01-05 5:10 ` Jason Wang
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=1419562425-20614-4-git-send-email-jasowang@redhat.com \
--to=jasowang@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mst@redhat.com \
--cc=rusty@rustcorp.com.au \
--cc=virtualization@lists.linux-foundation.org \
/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).