[v4,08/11] vdpa: Add eventfd for the vdpa callback

Message ID 20230323053043.35-9-xieyongji@bytedance.com
State New
Headers
Series VDUSE: Improve performance |

Commit Message

Yongji Xie March 23, 2023, 5:30 a.m. UTC
  Add eventfd for the vdpa callback so that user
can signal it directly instead of triggering the
callback. It will be used for vhost-vdpa case.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
---
 drivers/vhost/vdpa.c         | 2 ++
 drivers/virtio/virtio_vdpa.c | 1 +
 include/linux/vdpa.h         | 6 ++++++
 3 files changed, 9 insertions(+)
  

Comments

Jason Wang March 28, 2023, 6:17 a.m. UTC | #1
在 2023/3/23 13:30, Xie Yongji 写道:
> Add eventfd for the vdpa callback so that user
> can signal it directly instead of triggering the
> callback. It will be used for vhost-vdpa case.
>
> Signed-off-by: Xie Yongji <xieyongji@bytedance.com>


Acked-by: Jason Wang <jasowang@redhat.com>

Thanks


> ---
>   drivers/vhost/vdpa.c         | 2 ++
>   drivers/virtio/virtio_vdpa.c | 1 +
>   include/linux/vdpa.h         | 6 ++++++
>   3 files changed, 9 insertions(+)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 7be9d9d8f01c..9cd878e25cff 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -599,9 +599,11 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
>   		if (vq->call_ctx.ctx) {
>   			cb.callback = vhost_vdpa_virtqueue_cb;
>   			cb.private = vq;
> +			cb.trigger = vq->call_ctx.ctx;
>   		} else {
>   			cb.callback = NULL;
>   			cb.private = NULL;
> +			cb.trigger = NULL;
>   		}
>   		ops->set_vq_cb(vdpa, idx, &cb);
>   		vhost_vdpa_setup_vq_irq(v, idx);
> diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
> index f3826f42b704..2a095f37f26b 100644
> --- a/drivers/virtio/virtio_vdpa.c
> +++ b/drivers/virtio/virtio_vdpa.c
> @@ -196,6 +196,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
>   	/* Setup virtqueue callback */
>   	cb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;
>   	cb.private = info;
> +	cb.trigger = NULL;
>   	ops->set_vq_cb(vdpa, index, &cb);
>   	ops->set_vq_num(vdpa, index, virtqueue_get_vring_size(vq));
>   
> diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> index e52c9a37999c..0372b2e3d38a 100644
> --- a/include/linux/vdpa.h
> +++ b/include/linux/vdpa.h
> @@ -13,10 +13,16 @@
>    * struct vdpa_calllback - vDPA callback definition.
>    * @callback: interrupt callback function
>    * @private: the data passed to the callback function
> + * @trigger: the eventfd for the callback (Optional).
> + *           When it is set, the vDPA driver must guarantee that
> + *           signaling it is functional equivalent to triggering
> + *           the callback. Then vDPA parent can signal it directly
> + *           instead of triggering the callback.
>    */
>   struct vdpa_callback {
>   	irqreturn_t (*callback)(void *data);
>   	void *private;
> +	struct eventfd_ctx *trigger;
>   };
>   
>   /**
  

Patch

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 7be9d9d8f01c..9cd878e25cff 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -599,9 +599,11 @@  static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 		if (vq->call_ctx.ctx) {
 			cb.callback = vhost_vdpa_virtqueue_cb;
 			cb.private = vq;
+			cb.trigger = vq->call_ctx.ctx;
 		} else {
 			cb.callback = NULL;
 			cb.private = NULL;
+			cb.trigger = NULL;
 		}
 		ops->set_vq_cb(vdpa, idx, &cb);
 		vhost_vdpa_setup_vq_irq(v, idx);
diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
index f3826f42b704..2a095f37f26b 100644
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c
@@ -196,6 +196,7 @@  virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
 	/* Setup virtqueue callback */
 	cb.callback = callback ? virtio_vdpa_virtqueue_cb : NULL;
 	cb.private = info;
+	cb.trigger = NULL;
 	ops->set_vq_cb(vdpa, index, &cb);
 	ops->set_vq_num(vdpa, index, virtqueue_get_vring_size(vq));
 
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index e52c9a37999c..0372b2e3d38a 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -13,10 +13,16 @@ 
  * struct vdpa_calllback - vDPA callback definition.
  * @callback: interrupt callback function
  * @private: the data passed to the callback function
+ * @trigger: the eventfd for the callback (Optional).
+ *           When it is set, the vDPA driver must guarantee that
+ *           signaling it is functional equivalent to triggering
+ *           the callback. Then vDPA parent can signal it directly
+ *           instead of triggering the callback.
  */
 struct vdpa_callback {
 	irqreturn_t (*callback)(void *data);
 	void *private;
+	struct eventfd_ctx *trigger;
 };
 
 /**