Now we tackle the functions also called from interrupt handlers.
- intel_check_page_flip is exclusively called from irq handlers, so a
plain spin_lock is all we need. In i915_irq.c we have the convention
to give all such functions an _irq_handler postfix, but that would
look strange and als be a bit a misleading name. I've opted for a
WARN_ON(!in_irq()) instead.
- The other two places left are called both from interrupt handlers
and from our reset work, so need the full irqsave dance. Annotate
them with a short comment.
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
drivers/gpu/drm/i915/intel_display.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c
b/drivers/gpu/drm/i915/intel_display.c
index dcbefe510a2a..d120dfff3841 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9385,6 +9385,10 @@ static void do_intel_finish_page_flip(struct drm_device
*dev,
if (intel_crtc == NULL)
return;
+ /*
+ * This is called both by irq handlers and the reset code (to complete
+ * lost pageflips) so needs the full irqsave spinlocks.
+ */
spin_lock_irqsave(&dev->event_lock, flags);
work = intel_crtc->unpin_work;
@@ -9466,7 +9470,12 @@ void intel_prepare_page_flip(struct drm_device *dev, int
plane)
to_intel_crtc(dev_priv->plane_to_crtc_mapping[plane]);
unsigned long flags;
- /* NB: An MMIO update of the plane base pointer will also
+
+ /*
+ * This is called both by irq handlers and the reset code (to complete
+ * lost pageflips) so needs the full irqsave spinlocks.
+ *
+ * NB: An MMIO update of the plane base pointer will also
* generate a page-flip completion irq, i.e. every modeset
* is also accompanied by a spurious intel_prepare_page_flip().
*/
@@ -9923,18 +9932,19 @@ void intel_check_page_flip(struct drm_device *dev, int
pipe)
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
- unsigned long flags;
+
+ WARN_ON(!in_irq());
if (crtc == NULL)
return;
- spin_lock_irqsave(&dev->event_lock, flags);
+ spin_lock(&dev->event_lock);
if (intel_crtc->unpin_work && __intel_pageflip_stall_check(dev, crtc)) {
WARN_ONCE(1, "Kicking stuck page flip: queued at %d, now %d\n",
intel_crtc->unpin_work->flip_queued_vblank,
drm_vblank_count(dev, pipe));
page_flip_completed(intel_crtc);
}
- spin_unlock_irqrestore(&dev->event_lock, flags);
+ spin_unlock(&dev->event_lock);
}
static int intel_crtc_page_flip(struct drm_crtc *crtc,
--
1.9.3
