[Intel-gfx] [PATCH 05/21] drm/i915: Invalidate fenced read domains upon flush

[Chris Wilson]

Whenever we finish reading an object through a fence, for safety we
clear any GPU read domain and so invalidate any TLBs associated with
the fenced region upon its next use. As we now always flush writes
through an existing fence before it is released and then trigger the
invalidation of the GPU domains should we ever re-use it again on the
GPU, we no longer need to compare and force the invalidation if the
fenced access changes in move_to_gpu().

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/i915_gem.c            |    2 ++
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |    5 ++---
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 6b6bde0..0ccd3ab 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2536,6 +2536,8 @@ i915_gem_object_flush_fence(struct drm_i915_gem_object *obj,
 				return ret;
 		}
 
+		 /* Invalidate the GPU TLBs for any future reads */
+		obj->base.read_domains &= ~I915_GEM_GPU_DOMAINS;
 		obj->fenced_gpu_access = false;
 	}
 
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index a07911f..0010aee 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -172,9 +172,8 @@ i915_gem_object_set_to_gpu_domain(struct drm_i915_gem_object *obj,
 	 * write domain
 	 */
 	if (obj->base.write_domain &&
-	    (((obj->base.write_domain != obj->base.pending_read_domains ||
-	       obj->ring != ring)) ||
-	     (obj->fenced_gpu_access && !obj->pending_fenced_gpu_access))) {
+	    (obj->base.write_domain != obj->base.pending_read_domains ||
+	     obj->ring != ring)) {
 		flush_domains |= obj->base.write_domain;
 		invalidate_domains |=
 			obj->base.pending_read_domains & ~obj->base.write_domain;
-- 
1.7.4.1