drm/vkms: WARN when hrtimer_forward_now fails

Add a warn to verify the hrtimer_forward_now return and changes
ret_overrun from int to u64 to match the return value provided by
hrtimer_forward_now.

Signed-off-by: Shayenne Moura <shayenneluzmoura@gmail.com>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190206200813.d5w7gjpepoeeadiy@smtp.gmail.com

diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
index 5a09561..734a3e1 100644 (file)
--- a/drivers/gpu/drm/vkms/vkms_crtc.c
+++ b/drivers/gpu/drm/vkms/vkms_crtc.c
@@ -16,7 +16,7 @@ static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
                                                  vblank_hrtimer);
        struct drm_crtc *crtc = &output->crtc;
        struct vkms_crtc_state *state = to_vkms_crtc_state(crtc->state);
-       int ret_overrun;
+       u64 ret_overrun;
        bool ret;
 
        spin_lock(&output->lock);
@@ -43,6 +43,8 @@ static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
 
        ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer,
                                          output->period_ns);
+       WARN_ON(ret_overrun != 1);
+
        spin_unlock(&output->lock);
 
        return HRTIMER_RESTART;