drm/i915/ringbuffer: Simplify the ring irq refcounting
... and move it under the spinlock to gain the appropriate memory
barriers.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=32752
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 3bff7fb..13cad98 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -521,22 +521,20 @@
render_ring_get_irq(struct intel_ring_buffer *ring)
{
struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
if (!dev->irq_enabled)
return false;
- if (atomic_inc_return(&ring->irq_refcount) == 1) {
- drm_i915_private_t *dev_priv = dev->dev_private;
- unsigned long irqflags;
-
- spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+ spin_lock(&dev_priv->irq_lock);
+ if (ring->irq_refcount++ == 0) {
if (HAS_PCH_SPLIT(dev))
ironlake_enable_irq(dev_priv,
GT_PIPE_NOTIFY | GT_USER_INTERRUPT);
else
i915_enable_irq(dev_priv, I915_USER_INTERRUPT);
- spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}
+ spin_unlock(&dev_priv->irq_lock);
return true;
}
@@ -545,20 +543,18 @@
render_ring_put_irq(struct intel_ring_buffer *ring)
{
struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
- if (atomic_dec_and_test(&ring->irq_refcount)) {
- drm_i915_private_t *dev_priv = dev->dev_private;
- unsigned long irqflags;
-
- spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+ spin_lock(&dev_priv->irq_lock);
+ if (--ring->irq_refcount == 0) {
if (HAS_PCH_SPLIT(dev))
ironlake_disable_irq(dev_priv,
GT_USER_INTERRUPT |
GT_PIPE_NOTIFY);
else
i915_disable_irq(dev_priv, I915_USER_INTERRUPT);
- spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}
+ spin_unlock(&dev_priv->irq_lock);
}
void intel_ring_setup_status_page(struct intel_ring_buffer *ring)
@@ -619,18 +615,15 @@
ring_get_irq(struct intel_ring_buffer *ring, u32 flag)
{
struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
if (!dev->irq_enabled)
return false;
- if (atomic_inc_return(&ring->irq_refcount) == 1) {
- drm_i915_private_t *dev_priv = dev->dev_private;
- unsigned long irqflags;
-
- spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+ spin_lock(&dev_priv->irq_lock);
+ if (ring->irq_refcount++ == 0)
ironlake_enable_irq(dev_priv, flag);
- spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
- }
+ spin_unlock(&dev_priv->irq_lock);
return true;
}
@@ -639,35 +632,30 @@
ring_put_irq(struct intel_ring_buffer *ring, u32 flag)
{
struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
- if (atomic_dec_and_test(&ring->irq_refcount)) {
- drm_i915_private_t *dev_priv = dev->dev_private;
- unsigned long irqflags;
-
- spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+ spin_lock(&dev_priv->irq_lock);
+ if (--ring->irq_refcount == 0)
ironlake_disable_irq(dev_priv, flag);
- spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
- }
+ spin_unlock(&dev_priv->irq_lock);
}
static bool
gen6_ring_get_irq(struct intel_ring_buffer *ring, u32 gflag, u32 rflag)
{
struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
if (!dev->irq_enabled)
return false;
- if (atomic_inc_return(&ring->irq_refcount) == 1) {
- drm_i915_private_t *dev_priv = dev->dev_private;
- unsigned long irqflags;
-
- spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+ spin_lock(&dev_priv->irq_lock);
+ if (ring->irq_refcount++ == 0) {
ring->irq_mask &= ~rflag;
I915_WRITE_IMR(ring, ring->irq_mask);
ironlake_enable_irq(dev_priv, gflag);
- spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}
+ spin_unlock(&dev_priv->irq_lock);
return true;
}
@@ -676,17 +664,15 @@
gen6_ring_put_irq(struct intel_ring_buffer *ring, u32 gflag, u32 rflag)
{
struct drm_device *dev = ring->dev;
+ drm_i915_private_t *dev_priv = dev->dev_private;
- if (atomic_dec_and_test(&ring->irq_refcount)) {
- drm_i915_private_t *dev_priv = dev->dev_private;
- unsigned long irqflags;
-
- spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
+ spin_lock(&dev_priv->irq_lock);
+ if (--ring->irq_refcount == 0) {
ring->irq_mask |= rflag;
I915_WRITE_IMR(ring, ring->irq_mask);
ironlake_disable_irq(dev_priv, gflag);
- spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}
+ spin_unlock(&dev_priv->irq_lock);
}
static bool