[PATCH] drm: Assert correct locking for drm_send_vblank_event

[Daniel Vetter]

The comment says that the caller must hold the dev->event_lock
spinlock, so let's enforce this.

A quick audit over all driver shows that except for the one place in
i915 which motivated this all callers fullfill this requirement
already.

Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: dri-devel at lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/drm_irq.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 80ff94ada75e..bf248eb9ffb2 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -907,6 +907,9 @@ void drm_send_vblank_event(struct drm_device *dev, int crtc,
 {
 	struct timeval now;
 	unsigned int seq;
+
+	assert_spin_locked(&dev->event_lock);
+
 	if (crtc >= 0) {
 		seq = drm_vblank_count_and_time(dev, crtc, &now);
 	} else {
-- 
1.9.3