Re: [PATCH 3/9] vhost-user: add VHOST_USER_SET_LOG_FD command

[Stefano Brivio <sbrivio@redhat.com>]

On Thu, 19 Dec 2024 12:13:54 +0100
Laurent Vivier <lvivier@redhat.com> wrote:

> VHOST_USER_SET_LOG_FD is an optional message with an eventfd
> in ancillary data, it may be used to inform the front-end that the
> log has been modified.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>  vhost_user.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  vhost_user.h |  1 +
>  virtio.h     |  2 ++
>  3 files changed, 59 insertions(+)
> 
> diff --git a/vhost_user.c b/vhost_user.c
> index 48226a8b7686..ce4373d9eeca 100644
> --- a/vhost_user.c
> +++ b/vhost_user.c
> @@ -504,6 +504,57 @@ static bool vu_set_mem_table_exec(struct vu_dev *vdev,
>  	return false;
>  }
>  
> +/**
> + * vu_close_log() - Close the logging file descriptor
> + * @vdev:	vhost-user device
> + */
> +static void vu_close_log(struct vu_dev *vdev)
> +{
> +	if (vdev->log_call_fd != -1) {
> +		close(vdev->log_call_fd);
> +		vdev->log_call_fd = -1;
> +	}
> +}
> +
> +/**
> + * vu_log_kick() - Inform the front-end that the log has been modified
> + * @vdev:	vhost-user device
> + */
> +/* cppcheck-suppress unusedFunction */
> +void vu_log_kick(const struct vu_dev *vdev)
> +{
> +	if (vdev->log_call_fd != -1) {
> +		int rc;
> +
> +		rc = eventfd_write(vdev->log_call_fd, 1);
> +		if (rc == -1)
> +			die_perror("vhost-user kick eventfd_write()");
> +	}
> +}
> +
> +/**
> + * vu_set_log_fd_exec() -- Set the eventfd used to report logging update

Nit: single '-' between function name and comment.

-- 
Stefano