[Intel-gfx] [PATCH 3/4] drm/i915: Lazily migrate the objects after hibernation

[Chris Wilson]

Now that we mark the object domains for having been restored from the
hibernation image, we not need to flush everything during resume and
can instead rely on the normal domain tracking to flush only when
required. The only caveat here are objects that are pinned for use by
the hardware, whose contents must be coherent for when the device
resumes reading from then (shortly afterwards with the driver assuming
the objects are in the correct domain).

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Imre Deak <imre.deak at intel.com>
Cc: David Weinehall <david.weinehall at intel.com>
---
 drivers/gpu/drm/i915/i915_gem_gtt.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 5fb14c835543..319f3b459b3e 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -3245,7 +3245,6 @@ void i915_gem_restore_gtt_mappings(struct drm_device *dev)
 	struct i915_ggtt *ggtt = &dev_priv->ggtt;
 	struct drm_i915_gem_object *obj;
 	struct i915_vma *vma;
-	bool flush;
 
 	i915_check_and_clear_faults(dev_priv);
 
@@ -3255,19 +3254,16 @@ void i915_gem_restore_gtt_mappings(struct drm_device *dev)
 
 	/* Cache flush objects bound into GGTT and rebind them. */
 	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
-		flush = false;
 		list_for_each_entry(vma, &obj->vma_list, obj_link) {
 			if (vma->vm != &ggtt->base)
 				continue;
 
 			WARN_ON(i915_vma_bind(vma, obj->cache_level,
 					      PIN_UPDATE));
-
-			flush = true;
 		}
 
-		if (flush)
-			i915_gem_clflush_object(obj, obj->pin_display);
+		if (obj->pin_display)
+			WARN_ON(i915_gem_object_set_to_gtt_domain(obj, false));
 	}
 
 	if (INTEL_INFO(dev)->gen >= 8) {
-- 
2.8.1