[PATCH 182/241] drm/i915: Use cpu relocations if the object is in the GTT but not mappable

Herton Ronaldo Krzesinski herton.krzesinski at canonical.com
Thu Dec 13 13:59:07 UTC 2012 -stable review patch.  If anyone has any objections, please let me know.


From: Chris Wilson <chris at chris-wilson.co.uk>

commit 504c7267a1e84b157cbd7e9c1b805e1bc0c2c846 upstream.

This prevents the case of unbinding the object in order to process the
relocations through the GTT and then rebinding it only to then proceed
to use cpu relocations as the object is now in the CPU write domain. By
choosing to use cpu relocations up front, we can therefore avoid the
rebind penalty.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 974a9f1..3debf95 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -269,6 +269,7 @@ eb_destroy(struct eb_objects *eb)
 static inline int use_cpu_reloc(struct drm_i915_gem_object *obj)
 	return (obj->base.write_domain == I915_GEM_DOMAIN_CPU ||
+		!obj->map_and_fenceable ||
 		obj->cache_level != I915_CACHE_NONE);

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