[PATCH 6/6] vhost_net: don't poll on -EFAULT

From: Jason Wang
Date: Mon Apr 16 2012 - 02:17:16 EST

Currently, we restart tx polling unconditionally when sendmsg()
fails. This would cause unnecessary wakeups of vhost wokers as it's
only needed when the socket send buffer were exceeded. Fix this by
restart the tx polling only when sendmsg() returns value other than

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
drivers/vhost/net.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 29abd65..035fa95 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -262,7 +262,8 @@ static void handle_tx(struct vhost_net *net)
vhost_discard_vq_desc(vq, 1);
- tx_poll_start(net, sock);
+ if (err != -EFAULT)
+ tx_poll_start(net, sock);
if (err != len)

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