[Intel-gfx] [PATCH] drm/i915: Stop discarding GTT cache-domain on unbind vma

[Chris Wilson]

Since

commit 43566dedde54f9729113f5f9fde77d53e75e61e9
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Fri Jan 2 16:29:29 2015 +0530

    drm/i915: Broaden application of set-domain(GTT)

we allowed objects to be in the GTT domain, but unbound. Therefore
removing the GTT cache domain when removing the GGTT vma is no longer
semantically correct.

An unfortunate side-effect is we lose the wondrously named
i915_gem_object_finish_gtt(), not to be confused with
i915_gem_gtt_finish_object()!

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Akash Goel <akash.goel at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
---
 drivers/gpu/drm/i915/i915_gem.c | 22 +++-------------------
 1 file changed, 3 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 6ffc4a619849..1ea94aec41d1 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3171,23 +3171,6 @@ i915_gem_object_sync(struct drm_i915_gem_object *obj,
 	return 0;
 }
 
-static void i915_gem_object_finish_gtt(struct drm_i915_gem_object *obj)
-{
-	/* Force a pagefault for domain tracking on next user access */
-	i915_gem_release_mmap(obj);
-
-	if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0)
-		return;
-
-	/* Wait for any direct GTT access to complete */
-	mb();
-
-	obj->base.read_domains &= ~I915_GEM_DOMAIN_GTT;
-	obj->base.write_domain &= ~I915_GEM_DOMAIN_GTT;
-
-	trace_i915_gem_object_change_domain(obj);
-}
-
 int i915_vma_unbind(struct i915_vma *vma)
 {
 	struct drm_i915_gem_object *obj = vma->obj;
@@ -3219,12 +3202,13 @@ int i915_vma_unbind(struct i915_vma *vma)
 	 */
 
 	if (vma->is_ggtt && vma->ggtt_view.type == I915_GGTT_VIEW_NORMAL) {
-		i915_gem_object_finish_gtt(obj);
-
 		/* release the fence reg _after_ flushing */
 		ret = i915_gem_object_put_fence(obj);
 		if (ret)
 			return ret;
+
+		/* Force a pagefault for domain tracking on next user access */
+		i915_gem_release_mmap(obj);
 	}
 
 	trace_i915_vma_unbind(vma);
-- 
2.1.4