From 526d3e7ff515582eaf7cf5d9da2a11bf681204e6 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Fri, 4 Mar 2016 06:24:51 -0500 Subject: vhost: introduce vhost_has_work() This path introduces a helper which can give a hint for whether or not there's a work queued in the work list. This could be used for busy polling code to exit the busy loop. Signed-off-by: Jason Wang Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/vhost/vhost.c') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 328c54ab0154..596de212fe7e 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -263,6 +263,13 @@ void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) } EXPORT_SYMBOL_GPL(vhost_work_queue); +/* A lockless hint for busy polling code to exit the loop */ +bool vhost_has_work(struct vhost_dev *dev) +{ + return !list_empty(&dev->work_list); +} +EXPORT_SYMBOL_GPL(vhost_has_work); + void vhost_poll_queue(struct vhost_poll *poll) { vhost_work_queue(poll->dev, &poll->work); -- cgit v1.2.3