Otherwise it seems like we can get stuck with concurrent waiters.
Right now this /shouldn't/ be a problem, since all pending pageflip
waiters are serialized by the one mode_config.mutex, so there's at
most on waiter. But better paranoid than sorry, since this is tricky
code.
v2: WARN_ON(waitqueue_active) before waiting, as suggested by Chris
Wilson.
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
drivers/gpu/drm/i915/intel_display.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c
b/drivers/gpu/drm/i915/intel_display.c
index 9095d41..eb61fe9 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2221,6 +2221,8 @@ intel_finish_fb(struct drm_framebuffer *old_fb)
bool was_interruptible = dev_priv->mm.interruptible;
int ret;
+ WARN_ON(waitqueue_active(&dev_priv->pending_flip_queue));
+
wait_event(dev_priv->pending_flip_queue,
atomic_read(&dev_priv->mm.wedged) ||
atomic_read(&obj->pending_flip) == 0);
@@ -2888,6 +2890,8 @@ static void intel_crtc_wait_for_pending_flips(struct
drm_crtc *crtc)
if (crtc->fb == NULL)
return;
+ WARN_ON(waitqueue_active(&dev_priv->pending_flip_queue));
+
wait_event(dev_priv->pending_flip_queue,
!intel_crtc_has_pending_flip(crtc));
@@ -6833,7 +6837,7 @@ static void do_intel_finish_page_flip(struct drm_device
*dev,
obj = work->old_fb_obj;
- wake_up(&dev_priv->pending_flip_queue);
+ wake_up_all(&dev_priv->pending_flip_queue);
queue_work(dev_priv->wq, &work->work);
--
1.7.10.4
