drm/i915: Use engine->context_pin() to report the intel_ring
Since unifying ringbuffer/execlist submission to use
engine->pin_context, we ensure that the intel_ring is available before
we start constructing the request. We can therefore move the assignment
of the request->ring to the central i915_gem_request_alloc() and not
require it in every engine->request_alloc() callback. Another small step
towards simplification (of the core, but at a cost of handling error
pointers in less important callers of engine->pin_context).
v2: Rearrange a few branches to reduce impact of PTR_ERR() on gcc's code
generation.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Oscar Mateo <oscar.mateo@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170504093308.4137-1-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c
index 9074303..10361c7 100644
--- a/drivers/gpu/drm/i915/i915_gem_request.c
+++ b/drivers/gpu/drm/i915/i915_gem_request.c
@@ -551,6 +551,7 @@ i915_gem_request_alloc(struct intel_engine_cs *engine,
{
struct drm_i915_private *dev_priv = engine->i915;
struct drm_i915_gem_request *req;
+ struct intel_ring *ring;
int ret;
lockdep_assert_held(&dev_priv->drm.struct_mutex);
@@ -565,9 +566,10 @@ i915_gem_request_alloc(struct intel_engine_cs *engine,
* GGTT space, so do this first before we reserve a seqno for
* ourselves.
*/
- ret = engine->context_pin(engine, ctx);
- if (ret)
- return ERR_PTR(ret);
+ ring = engine->context_pin(engine, ctx);
+ if (IS_ERR(ring))
+ return ERR_CAST(ring);
+ GEM_BUG_ON(!ring);
ret = reserve_seqno(engine);
if (ret)
@@ -633,6 +635,7 @@ i915_gem_request_alloc(struct intel_engine_cs *engine,
req->i915 = dev_priv;
req->engine = engine;
req->ctx = ctx;
+ req->ring = ring;
/* No zalloc, must clear what we need by hand */
req->global_seqno = 0;