On Thu, Oct 22, 2015 at 01:27:28AM -0400, Jason Wang wrote: > This path introduces a helper which can give a hint for whether or not > there's a work queued in the work list. > > Signed-off-by: Jason Wang <jasow...@redhat.com> > --- > drivers/vhost/vhost.c | 6 ++++++ > drivers/vhost/vhost.h | 1 + > 2 files changed, 7 insertions(+) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index eec2f11..d42d11e 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -245,6 +245,12 @@ void vhost_work_queue(struct vhost_dev *dev, struct > vhost_work *work) > } > EXPORT_SYMBOL_GPL(vhost_work_queue); > > +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);
This doesn't take a lock so it's unreliable. I think it's ok in this case since it's just an optimization - but pls document this. > diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h > index 4772862..ea0327d 100644 > --- a/drivers/vhost/vhost.h > +++ b/drivers/vhost/vhost.h > @@ -37,6 +37,7 @@ struct vhost_poll { > > void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn); > void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work); > +bool vhost_has_work(struct vhost_dev *dev); > > void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, > unsigned long mask, struct vhost_dev *dev); > -- > 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/