Re: [PATCH 7/7] libvhost-user: Switch to unsigned int for inuse field in struct VuVirtq

[Philippe Mathieu-Daudé]

On 19/12/22 18:53, Marcel Holtmann wrote:
> It seems there is no need to keep the inuse field signed and end up with
> compiler warnings for sign-compare.
>
>    CC       libvhost-user.o
> libvhost-user.c: In function ‘vu_queue_pop’:
> libvhost-user.c:2763:19: error: comparison of integer expressions of different 
> signedness: ‘int’ and ‘unsigned int’ [-Werror=sign-compare]
>   2763 |     if (vq->inuse >= vq->vring.num) {
>        |                   ^~
> libvhost-user.c: In function ‘vu_queue_rewind’:
> libvhost-user.c:2808:13: error: comparison of integer expressions of different 
> signedness: ‘unsigned int’ and ‘int’ [-Werror=sign-compare]
>   2808 |     if (num > vq->inuse) {
>        |             ^
>
> Instead of casting the comparision to unsigned int, just make the inuse
> field unsigned int in the fist place.
>
> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
> ---
>   subprojects/libvhost-user/libvhost-user.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/subprojects/libvhost-user/libvhost-user.h 
> b/subprojects/libvhost-user/libvhost-user.h
> index aea7ec5061d5..8cda9b8f577a 100644
> --- a/subprojects/libvhost-user/libvhost-user.h
> +++ b/subprojects/libvhost-user/libvhost-user.h
> @@ -343,7 +343,7 @@ typedef struct VuVirtq {
>       /* Notification enabled? */
>       bool notification;
>   
> -    int inuse;
> +    unsigned int inuse;

Another use in subprojects/libvduse/libvduse.c.

Possibly both could be renamed refcount which is more meaningful.

Anyhow,
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>