[Intel-gfx] [PATCH 04/40] drm/i915: Check for no-op priority changes first

[Chris Wilson]

In all likelihood, the priority and node are already in the CPU cache
and by checking them first, we can avoid having to chase the
*request->hwsp for the current breadcrumb.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
---
 drivers/gpu/drm/i915/i915_scheduler.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c
index f32d0ee6d58c..5581c5004ff0 100644
--- a/drivers/gpu/drm/i915/i915_scheduler.c
+++ b/drivers/gpu/drm/i915/i915_scheduler.c
@@ -200,10 +200,10 @@ static void __i915_schedule(struct i915_sched_node *node,
 	lockdep_assert_held(&schedule_lock);
 	GEM_BUG_ON(prio == I915_PRIORITY_INVALID);
 
-	if (node_signaled(node))
+	if (prio <= READ_ONCE(node->attr.priority))
 		return;
 
-	if (prio <= READ_ONCE(node->attr.priority))
+	if (node_signaled(node))
 		return;
 
 	stack.signaler = node;
-- 
2.20.1