[PATCH RFC v5 net-next 5/6] vhost: let vhost_signal() returns whether signalled

Jason Wang
2015-02-09T08:40:07Z

Let vhost_signal() return whether or not vhost has injected an
interrupt to guest. This is used for interrupt coalescing
implementation to calculate the interval between two interrupts.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vhost.c | 7 +++++--
drivers/vhost/vhost.h | 2 +-
2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index cb807d0..20d6b84 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1480,11 +1480,14 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
}

/* This actually signals the guest, using eventfd. */
-void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
+bool vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
{
/* Signal the Guest tell them we used something up. */
- if (vq->call_ctx && vhost_notify(dev, vq))
+ if (vq->call_ctx && vhost_notify(dev, vq)) {
eventfd_signal(vq->call_ctx, 1);
+ return true;
+ }
+ return false;
}
EXPORT_SYMBOL_GPL(vhost_signal);

diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 8c1c792..a482563 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -148,7 +148,7 @@ void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
unsigned int id, int len);
void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
struct vring_used_elem *heads, unsigned count);
-void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
+bool vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);

--
1.8.3.1