drm/i915: Only hold a process-local lock whilst throttling.

Avoid cause latencies in other clients by not taking the global struct
mutex and moving the per-client request manipulation a local per-client
mutex. For example, this allows a compositor to schedule a page-flip
(through X) whilst an OpenGL application is monopolising the GPU.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index ce52101..d506da1 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -58,10 +58,9 @@
 			u32	flush_domains);
 	u32		(*add_request)(struct drm_device *dev,
 			struct intel_ring_buffer *ring,
-			struct drm_file *file_priv,
 			u32 flush_domains);
-	u32		(*get_gem_seqno)(struct drm_device *dev,
-			struct intel_ring_buffer *ring);
+	u32		(*get_seqno)(struct drm_device *dev,
+				     struct intel_ring_buffer *ring);
 	int		(*dispatch_gem_execbuffer)(struct drm_device *dev,
 			struct intel_ring_buffer *ring,
 			struct drm_i915_gem_execbuffer2 *exec,