drm/i915: Return a mask of the active rings in the high word of busy_ioctl
The intention is to help select which engine to use for copies with
interoperating clients - such as a GL client making a request to the X
server to perform a SwapBuffers, which may require copying from the
active GL back buffer to the X front buffer.
We choose to report a mask of the active rings to future proof the
interface against any changes which may allow for the object to reside
upon multiple rings.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: bikeshed away the write ring mask and add the explanation
Chris sent in a follow-up mail why we decided to use masks.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 5c4657a..4be0960 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3400,6 +3400,10 @@
ret = i915_gem_object_flush_active(obj);
args->busy = obj->active;
+ if (obj->ring) {
+ BUILD_BUG_ON(I915_NUM_RINGS > 16);
+ args->busy |= intel_ring_flag(obj->ring) << 16;
+ }
drm_gem_object_unreference(&obj->base);
unlock: