Re: [Qemu-devel] [PATCH] vhost-user: pass message as a pointer to process_message_reply()

[Marc-André Lureau]

On Wed, May 24, 2017 at 11:35 AM Maxime Coquelin <address@hidden>
wrote:

> process_message_reply() was recently updated to get full message
> content instead of only its request field.
>
> There is no need to copy all the struct content into the stack,
> so just pass its pointer.
>
> Cc: Zhiyong Yang <address@hidden>
> Fixes: 60cd11024f41 ("hw/virtio: fix vhost user fails to startup when MQ")
> Signed-off-by: Maxime Coquelin <address@hidden>
> ---
>  hw/virtio/vhost-user.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index b87a176..baf2487 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -162,11 +162,11 @@ fail:
>  }
>
>  static int process_message_reply(struct vhost_dev *dev,
> -                                 VhostUserMsg msg)
> +                                 VhostUserMsg *msg)
>

Can you make it const?


>  {
>      VhostUserMsg msg_reply;
>
> -    if ((msg.flags & VHOST_USER_NEED_REPLY_MASK) == 0) {
> +    if ((msg->flags & VHOST_USER_NEED_REPLY_MASK) == 0) {
>          return 0;
>      }
>
> @@ -174,10 +174,10 @@ static int process_message_reply(struct vhost_dev
> *dev,
>          return -1;
>      }
>
> -    if (msg_reply.request != msg.request) {
> +    if (msg_reply.request != msg->request) {
>          error_report("Received unexpected msg type."
>                       "Expected %d received %d",
> -                     msg.request, msg_reply.request);
> +                     msg->request, msg_reply.request);
>          return -1;
>      }
>
> @@ -324,7 +324,7 @@ static int vhost_user_set_mem_table(struct vhost_dev
> *dev,
>      }
>
>      if (reply_supported) {
> -        return process_message_reply(dev, msg);
> +        return process_message_reply(dev, &msg);
>      }
>
>      return 0;
> @@ -716,7 +716,7 @@ static int vhost_user_net_set_mtu(struct vhost_dev
> *dev, uint16_t mtu)
>
>      /* If reply_ack supported, slave has to ack specified MTU is valid */
>      if (reply_supported) {
> -        return process_message_reply(dev, msg);
> +        return process_message_reply(dev, &msg);
>      }
>
>      return 0;
> --
> 2.9.4
>
>
> --
Marc-André Lureau