[PATCH v3] drm: drm_vblank_cleanup: WARN when refcount > 0

[PrasannaKumar Muralidharan]

Hi,

On 13 October 2017 at 08:58, PrasannaKumar Muralidharan
<prasannatsmkumar at gmail.com> wrote:
> Warn when refcount > 0 in drm_vblank_cleanup.
>
> Signed-off-by: PrasannaKumar Muralidharan <prasannatsmkumar at gmail.com>
> ---
>  drivers/gpu/drm/drm_vblank.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
> index 70f2b95..3e61aeb 100644
> --- a/drivers/gpu/drm/drm_vblank.c
> +++ b/drivers/gpu/drm/drm_vblank.c
> @@ -405,6 +405,8 @@ void drm_vblank_cleanup(struct drm_device *dev)
>         for (pipe = 0; pipe < dev->num_crtcs; pipe++) {
>                 struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
>
> +               WARN_ON(atomic_read(&vblank->refcount) > 0);
> +
>                 WARN_ON(READ_ONCE(vblank->enabled) &&
>                         drm_core_check_feature(dev, DRIVER_MODESET));
>
> --
> 2.10.0
>

Looking at the CI logs, realised that the patch I used for testing had
a problem. I used drm_crtc_vblank_put instead of drm_crtc_vblank_get.
I do see that the warning is generated but I am wondering whether it
is correct.

If it is not correct I will resend corrected test patch. Please let me know.

Thanks,
PrasannaKumar