drm/i915/ringbuffer: Make IRQ refcnting atomic
In order to enforce the correct memory barriers for irq get/put, we need
to perform the actual counting using atomic operations.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 02e4dd8..2ddb98b 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1186,10 +1186,9 @@
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
struct intel_ring_buffer *ring = LP_RING(dev_priv);
- if (dev_priv->trace_irq_seqno == 0)
- ring->irq_get(ring);
-
- dev_priv->trace_irq_seqno = seqno;
+ if (dev_priv->trace_irq_seqno == 0 &&
+ ring->irq_get(ring))
+ dev_priv->trace_irq_seqno = seqno;
}
static int i915_wait_irq(struct drm_device * dev, int irq_nr)
@@ -1211,10 +1210,12 @@
if (master_priv->sarea_priv)
master_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;
- ring->irq_get(ring);
- DRM_WAIT_ON(ret, ring->irq_queue, 3 * DRM_HZ,
- READ_BREADCRUMB(dev_priv) >= irq_nr);
- ring->irq_put(ring);
+ ret = -ENODEV;
+ if (ring->irq_get(ring)) {
+ DRM_WAIT_ON(ret, ring->irq_queue, 3 * DRM_HZ,
+ READ_BREADCRUMB(dev_priv) >= irq_nr);
+ ring->irq_put(ring);
+ }
if (ret == -EBUSY) {
DRM_ERROR("EBUSY -- rec: %d emitted: %d\n",