? 2022/8/17 21:57, Guo Zhi ??:> Vsock uses buffers in order, and for tx driver doesn't have to
> know the length of the buffer. So we can do a batch for vsock if
> in order negotiated, only write one used ring for a batch of buffers
>
> Signed-off-by: Guo Zhi <qtxuning1999 at sjtu.edu.cn>
> ---
> drivers/vhost/vsock.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
> index 368330417bde..b0108009c39a 100644
> --- a/drivers/vhost/vsock.c
> +++ b/drivers/vhost/vsock.c
> @@ -500,6 +500,7 @@ static void vhost_vsock_handle_tx_kick(struct
vhost_work *work)
> int head, pkts = 0, total_len = 0;
> unsigned int out, in;
> bool added = false;
> + int last_head = -1;
>
> mutex_lock(&vq->mutex);
>
> @@ -551,10 +552,16 @@ static void vhost_vsock_handle_tx_kick(struct
vhost_work *work)
> else
> virtio_transport_free_pkt(pkt);
>
> - vhost_add_used(vq, head, 0);
> + if (!vhost_has_feature(vq, VIRTIO_F_IN_ORDER))
> + vhost_add_used(vq, head, 0);
> + else
> + last_head = head;
> added = true;
> } while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));
>
> + /* If in order feature negotiaged, we can do a batch to increase
performance */
> + if (vhost_has_feature(vq, VIRTIO_F_IN_ORDER) && last_head != -1)
> + vhost_add_used(vq, last_head, 0);
I may miss something but spec said "The device then skips forward in the
ring according to the size of the batch. ".
I don't see how it is done here.
Thanks
> no_more_replies:
> if (added)
> vhost_signal(&vsock->dev, vq);