drm/i915: Provide a cheap ggtt vma lookup
"We do fairly often lookup the ggtt vma for an obj." - Chris Wilson. As
such, provide a function to offer slightly cheaper access to the vma.
Not performance tested. By my quick estimation it saves at least 3
pointer dereferences from the existing mechanism.
This patch mostly matches code from Chris in
<20130911221430.GB7825@nuc-i3427.alporthouse.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 662c0ff..a3d43b2 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2030,6 +2030,9 @@
struct i915_vma *
i915_gem_obj_lookup_or_create_vma(struct drm_i915_gem_object *obj,
struct i915_address_space *vm);
+
+struct i915_vma *i915_gem_obj_to_ggtt(struct drm_i915_gem_object *obj);
+
/* Some GGTT VM helpers */
#define obj_to_ggtt(obj) \
(&((struct drm_i915_private *)(obj)->base.dev->dev_private)->gtt.base)
@@ -2066,7 +2069,6 @@
return i915_gem_object_pin(obj, obj_to_ggtt(obj), alignment,
map_and_fenceable, nonblocking);
}
-#undef obj_to_ggtt
/* i915_gem_context.c */
void i915_gem_context_init(struct drm_device *dev);