drm/i915: Write RING_TAIL once per-request

[~andy/linux] / drivers / gpu / drm / i915 / intel_ringbuffer.c

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 284afaf5d6ffc8357418b4202cc7ae5614f35e2c..686e5b23481def673fcf6d3c650cf18ceedc4b75 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -41,6 +41,16 @@ static inline int ring_space(struct intel_ring_buffer *ring)
        return space;
 }
 
+void __intel_ring_advance(struct intel_ring_buffer *ring)
+{
+       struct drm_i915_private *dev_priv = ring->dev->dev_private;
+
+       ring->tail &= ring->size - 1;
+       if (dev_priv->gpu_error.stop_rings & intel_ring_flag(ring))
+               return;
+       ring->write_tail(ring, ring->tail);
+}
+
 static int
 gen2_render_ring_flush(struct intel_ring_buffer *ring,
                       u32      invalidate_domains,
@@ -631,7 +641,7 @@ gen6_add_request(struct intel_ring_buffer *ring)
        intel_ring_emit(ring, I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
        intel_ring_emit(ring, ring->outstanding_lazy_seqno);
        intel_ring_emit(ring, MI_USER_INTERRUPT);
-       intel_ring_advance(ring);
+       __intel_ring_advance(ring);
 
        return 0;
 }
@@ -744,7 +754,7 @@ pc_render_add_request(struct intel_ring_buffer *ring)
        intel_ring_emit(ring, ring->scratch.gtt_offset | PIPE_CONTROL_GLOBAL_GTT);
        intel_ring_emit(ring, ring->outstanding_lazy_seqno);
        intel_ring_emit(ring, 0);
-       intel_ring_advance(ring);
+       __intel_ring_advance(ring);
 
        return 0;
 }
@@ -965,7 +975,7 @@ i9xx_add_request(struct intel_ring_buffer *ring)
        intel_ring_emit(ring, I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
        intel_ring_emit(ring, ring->outstanding_lazy_seqno);
        intel_ring_emit(ring, MI_USER_INTERRUPT);
-       intel_ring_advance(ring);
+       __intel_ring_advance(ring);
 
        return 0;
 }
@@ -1414,6 +1424,9 @@ static int ring_wait_for_space(struct intel_ring_buffer *ring, int n)
        if (ret != -ENOSPC)
                return ret;
 
+       /* force the tail write in case we have been skipping them */
+       __intel_ring_advance(ring);
+
        trace_i915_ring_wait_begin(ring);
        /* With GEM the hangcheck timer should kick us out of the loop,
         * leaving it early runs the risk of corrupting GEM state (due
@@ -1568,17 +1581,6 @@ void intel_ring_init_seqno(struct intel_ring_buffer *ring, u32 seqno)
        ring->hangcheck.seqno = seqno;
 }
 
-void intel_ring_advance(struct intel_ring_buffer *ring)
-{
-       struct drm_i915_private *dev_priv = ring->dev->dev_private;
-
-       ring->tail &= ring->size - 1;
-       if (dev_priv->gpu_error.stop_rings & intel_ring_flag(ring))
-               return;
-       ring->write_tail(ring, ring->tail);
-}
-
-
 static void gen6_bsd_ring_write_tail(struct intel_ring_buffer *ring,
                                     u32 value)
 {