[PATCH 09/11] drm/i915: dont perform a ttm move if creating in place

[Robert Beckett]

skip moving if we create the buffer in place

Signed-off-by: Robert Beckett <bob.beckett at collabora.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 40 +++++++++++++++++++++----
 1 file changed, 34 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index b26bde6a4bb9..ce09eb4aca0d 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -1136,7 +1136,8 @@ static int __i915_gem_ttm_object_init_with_placement(struct intel_memory_region
 						     resource_size_t size,
 						     resource_size_t page_size,
 						     unsigned int flags,
-						     struct ttm_placement *placement)
+						     struct ttm_placement *placement,
+						     bool allow_move)
 {
 	static struct lock_class_key lock_class;
 	struct drm_i915_private *i915 = mem->i915;
@@ -1145,6 +1146,8 @@ static int __i915_gem_ttm_object_init_with_placement(struct intel_memory_region
 		.no_wait_gpu = false,
 	};
 	enum ttm_bo_type bo_type;
+	struct ttm_buffer_object * ttm_bo = i915_gem_to_ttm(obj);
+	struct ttm_placement *init_placement = placement;
 	int ret;
 
 	drm_gem_private_object_init(&i915->drm, &obj->base, size);
@@ -1159,7 +1162,16 @@ static int __i915_gem_ttm_object_init_with_placement(struct intel_memory_region
 	bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device :
 		ttm_bo_type_kernel;
 
-	obj->base.vma_node.driver_private = i915_gem_to_ttm(obj);
+	obj->base.vma_node.driver_private = ttm_bo;
+
+	/*
+	 * default ttm behaviour is to allocate in system, then move the buffer
+	 * to the desired placement. If !allow_move, we allocate in system so that it
+	 * does not move the buffer, then directly replace the resource with one
+	 * allocted from the desired placement.
+	 */
+	if (!allow_move)
+		init_placement = &i915_sys_placement;
 
 	/* Forcing the page size is kernel internal only */
 	GEM_BUG_ON(page_size && obj->mm.n_placements);
@@ -1179,13 +1191,22 @@ static int __i915_gem_ttm_object_init_with_placement(struct intel_memory_region
 	 * Similarly, in delayed_destroy, we can't call ttm_bo_put()
 	 * until successful initialization.
 	 */
-	ret = ttm_bo_init_reserved(&i915->bdev, i915_gem_to_ttm(obj), size,
-				   bo_type, placement,
+	ret = ttm_bo_init_reserved(&i915->bdev, ttm_bo, size,
+				   bo_type, init_placement,
 				   page_size >> PAGE_SHIFT,
 				   &ctx, NULL, NULL, i915_ttm_bo_destroy);
 	if (ret)
 		return i915_ttm_err_to_gem(ret);
 
+	if (!allow_move) {
+		struct ttm_resource *res;
+		ret = ttm_bo_mem_space(ttm_bo, placement, &res, &ctx);
+		if (ret)
+			goto err_res;
+		ttm_resource_free(ttm_bo, &ttm_bo->resource);
+		ttm_bo->resource = res;
+	}
+
 	obj->ttm.created = true;
 	i915_gem_object_release_memory_region(obj);
 	i915_gem_object_init_memory_region(obj, mem);
@@ -1194,6 +1215,11 @@ static int __i915_gem_ttm_object_init_with_placement(struct intel_memory_region
 	i915_gem_object_unlock(obj);
 
 	return 0;
+
+err_res:
+	ttm_bo_unreserve(ttm_bo);
+	ttm_bo_put(ttm_bo);
+	return ret;
 }
 
 /**
@@ -1213,7 +1239,8 @@ int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
 {
 	return __i915_gem_ttm_object_init_with_placement(mem, obj, size,
 							 page_size, flags,
-							 &i915_sys_placement);
+							 &i915_sys_placement,
+							 true);
 }
 
 /**
@@ -1254,7 +1281,8 @@ int i915_gem_ttm_object_init_in_place(struct intel_memory_region *mem,
 
 	return __i915_gem_ttm_object_init_with_placement(mem, obj, size,
 							 page_size, flags,
-							 &placement);
+							 &placement,
+							 false);
 }
 
 static const struct intel_memory_region_ops ttm_system_region_ops = {
-- 
2.25.1