drm/i915: Only emit a flush if there is an outstanding gpu write

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 8685b9279029..e7733333767d 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2154,8 +2154,9 @@ static int i915_ring_idle(struct drm_device *dev,
         if (list_empty(&ring->gpu_write_list) && list_empty(&ring->active_list))
                 return 0;
 
-        i915_gem_flush_ring(dev, ring,
-                            I915_GEM_GPU_DOMAINS, I915_GEM_GPU_DOMAINS);
+        if (!list_empty(&ring->gpu_write_list))
+                i915_gem_flush_ring(dev, ring,
+                                    I915_GEM_GPU_DOMAINS, I915_GEM_GPU_DOMAINS);
         return i915_wait_request(dev,
                                  i915_gem_next_request_seqno(dev, ring),
                                  ring);