[Devel] [PATCH RH9 09/10] drivers/vhost: allow polls to be bound to workers via vqs

[Konstantin Khorenko]

On 16.08.2022 09:44, Andrey Zhadchenko wrote:
> Allow vhost polls to be associated with vqs so we can queue them
> on assigned workers.
> If polls are not associated with specific vqs queue them on the first
> worker.
> 
> https://jira.sw.ru/browse/PSBM-139414
> Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko at virtuozzo.com>
> ---
>   drivers/vhost/vhost.c | 24 ++++++++++++++++--------
>   drivers/vhost/vhost.h |  4 +++-
>   2 files changed, 19 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index 5cf3d8eccfff..cb25d5a022bc 100644
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -170,7 +170,7 @@ static int vhost_poll_wakeup(wait_queue_entry_t *wait, unsigned mode, int sync,
>   	if (!(key_to_poll(key) & poll->mask))
>   		return 0;
>   
> -	if (!poll->dev->use_worker)
> +	if (!poll->vq->dev->use_worker)
>   		work->fn(work);
>   	else
>   		vhost_poll_queue(poll);
> @@ -185,19 +185,27 @@ void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn)
>   }
>   EXPORT_SYMBOL_GPL(vhost_work_init);
>   
> -/* Init poll structure */
>   void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
>   		     __poll_t mask, struct vhost_dev *dev)
> +{
> +	vhost_poll_init_vq(poll, fn, mask, dev->vqs[0]);
> +}
> +EXPORT_SYMBOL_GPL(vhost_poll_init);
> +
> +
> +/* Init poll structure */
> +void vhost_poll_init_vq(struct vhost_poll *poll, vhost_work_fn_t fn,
> +		     __poll_t mask, struct vhost_virtqueue *vq)
>   {
>   	init_waitqueue_func_entry(&poll->wait, vhost_poll_wakeup);
>   	init_poll_funcptr(&poll->table, vhost_poll_func);
>   	poll->mask = mask;
> -	poll->dev = dev;
> +	poll->vq = vq;
>   	poll->wqh = NULL;
>   
>   	vhost_work_init(&poll->work, fn);
>   }
> -EXPORT_SYMBOL_GPL(vhost_poll_init);
> +EXPORT_SYMBOL_GPL(vhost_poll_init_vq);
>   
>   /* Start polling a file. We add ourselves to file's wait queue. The caller must
>    * keep a reference to a file until after vhost_poll_stop is called. */
> @@ -289,7 +297,7 @@ EXPORT_SYMBOL_GPL(vhost_work_flush_vq);
>    * locks that are also used by the callback. */
>   void vhost_poll_flush(struct vhost_poll *poll)
>   {
> -	vhost_work_dev_flush(poll->dev);
> +	vhost_work_flush_vq(poll->vq);
>   }
>   EXPORT_SYMBOL_GPL(vhost_poll_flush);
>   
> @@ -324,7 +332,7 @@ EXPORT_SYMBOL_GPL(vhost_has_work);
>   
>   void vhost_poll_queue(struct vhost_poll *poll)
>   {
> -	vhost_work_queue(poll->dev, &poll->work);
> +	vhost_work_queue_vq(poll->vq, &poll->work);
>   }
>   EXPORT_SYMBOL_GPL(vhost_poll_queue);
>   
> @@ -573,8 +581,8 @@ void vhost_dev_init(struct vhost_dev *dev,
>   		mutex_init(&vq->mutex);
>   		vhost_vq_reset(dev, vq);
>   		if (vq->handle_kick)
> -			vhost_poll_init(&vq->poll, vq->handle_kick,
> -					EPOLLIN, dev);
> +			vhost_poll_init_vq(&vq->poll, vq->handle_kick,
> +					   EPOLLIN, vq);
>   	}
>   }
>   EXPORT_SYMBOL_GPL(vhost_dev_init);
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> index dc7428c26cbe..4182fd7fceaf 100644
> --- a/drivers/vhost/vhost.h
> +++ b/drivers/vhost/vhost.h
> @@ -40,7 +40,7 @@ struct vhost_poll {
>   	wait_queue_entry_t	wait;
>   	struct vhost_work	work;
>   	__poll_t		mask;
> -	struct vhost_dev	*dev;
> +	struct vhost_virtqueue	*vq;
>   };
>   
>   void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
> @@ -49,6 +49,8 @@ bool vhost_has_work(struct vhost_dev *dev);
>   
>   void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
>   		     __poll_t mask, struct vhost_dev *dev);
> +void vhost_poll_init_vq(struct vhost_poll *poll, vhost_work_fn_t fn,
> +		     __poll_t mask, struct vhost_virtqueue *vq);
>   int vhost_poll_start(struct vhost_poll *poll, struct file *file);
>   void vhost_poll_stop(struct vhost_poll *poll);
>   void vhost_poll_flush(struct vhost_poll *poll);

LGTM