Re: [PATCH] drm/vblank: Fix -Wformat compile warnings on some arches

From: Sam Ravnborg
Date: Thu May 21 2020 - 17:09:31 EST


On Thu, May 21, 2020 at 04:46:47PM -0400, Lyude Paul wrote:
> On some architectures like ppc64le and aarch64, compiling with
> -Wformat=1 will throw the following warnings:
>
> In file included from drivers/gpu/drm/drm_vblank.c:33:
> drivers/gpu/drm/drm_vblank.c: In function 'drm_update_vblank_count':
> drivers/gpu/drm/drm_vblank.c:273:16: warning: format '%llu' expects
> argument of type 'long long unsigned int', but argument 4 has type
> 'long int' [-Wformat=]
> DRM_DEBUG_VBL("updating vblank count on crtc %u:"
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ./include/drm/drm_print.h:407:22: note: in definition of macro
> 'DRM_DEBUG_VBL'
> drm_dbg(DRM_UT_VBL, fmt, ##__VA_ARGS__)
> ^~~
> drivers/gpu/drm/drm_vblank.c:274:22: note: format string is defined here
> " current=%llu, diff=%u, hw=%u hw_last=%u\n",
> ~~~^
> %lu
>
> So, fix that with a typecast.
>
> Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
> Co-developed-by: Dave Airlie <airlied@xxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_vblank.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
> index acb3c3f65b579..1a96db2dd16fa 100644
> --- a/drivers/gpu/drm/drm_vblank.c
> +++ b/drivers/gpu/drm/drm_vblank.c
> @@ -342,7 +342,7 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
>
> DRM_DEBUG_VBL("updating vblank count on crtc %u:"
> " current=%llu, diff=%u, hw=%u hw_last=%u\n",
> - pipe, atomic64_read(&vblank->count), diff,
> + pipe, (unsigned long long)atomic64_read(&vblank->count), diff,
> cur_vblank, vblank->last);

While touching this you could consider introducing drm_dbg_vbl().
An maybe as a follow-up patch replace all logging in this file with the drm_* variants.

Sam

>
> if (diff == 0) {
> --
> 2.26.2
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@xxxxxxxxxxxxxxxxxxxxx
> https://lists.freedesktop.org/mailman/listinfo/dri-devel