drm/i915: Pass i915_sched_node around internally

To simplify the next patch, update bump_priority and schedule to accept
the internal i915_sched_ndoe directly and not expect a request pointer.

add/remove: 0/0 grow/shrink: 2/1 up/down: 8/-15 (-7)
Function                                     old     new   delta
i915_schedule_bump_priority                  109     113      +4
i915_schedule                                 50      54      +4
__i915_schedule                              922     907     -15

v2: Adopt node for the old rq local, since it no longer is a request but
the origin node.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190513120102.29660-2-chris@chris-wilson.co.uk
(cherry picked from commit 52c76fb1)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drivers/gpu/drm/i915/i915_scheduler.c

@@ -175,7 +175,7 @@ static bool inflight(const struct i915_request *rq,
 	return active->hw_context == rq->hw_context;
 }
 
-static void __i915_schedule(struct i915_request *rq,
+static void __i915_schedule(struct i915_sched_node *node,
 			    const struct i915_sched_attr *attr)
 {
 	struct intel_engine_cs *engine;
@@ -189,13 +189,13 @@ static void __i915_schedule(struct i915_request *rq,
 	lockdep_assert_held(&schedule_lock);
 	GEM_BUG_ON(prio == I915_PRIORITY_INVALID);
 
-	if (i915_request_completed(rq))
+	if (node_signaled(node))
 		return;
 
-	if (prio <= READ_ONCE(rq->sched.attr.priority))
+	if (prio <= READ_ONCE(node->attr.priority))
 		return;
 
-	stack.signaler = &rq->sched;
+	stack.signaler = node;
 	list_add(&stack.dfs_link, &dfs);
 
 	/*
@@ -246,9 +246,9 @@ static void __i915_schedule(struct i915_request *rq,
 	 * execlists_submit_request()), we can set our own priority and skip
 	 * acquiring the engine locks.
 	 */
-	if (rq->sched.attr.priority == I915_PRIORITY_INVALID) {
-		GEM_BUG_ON(!list_empty(&rq->sched.link));
-		rq->sched.attr = *attr;
+	if (node->attr.priority == I915_PRIORITY_INVALID) {
+		GEM_BUG_ON(!list_empty(&node->link));
+		node->attr = *attr;
 
 		if (stack.dfs_link.next == stack.dfs_link.prev)
 			return;
@@ -257,15 +257,14 @@ static void __i915_schedule(struct i915_request *rq,
 	}
 
 	memset(&cache, 0, sizeof(cache));
-	engine = rq->engine;
+	engine = node_to_request(node)->engine;
 	spin_lock(&engine->timeline.lock);
 
 	/* Fifo and depth-first replacement ensure our deps execute before us */
 	list_for_each_entry_safe_reverse(dep, p, &dfs, dfs_link) {
-		struct i915_sched_node *node = dep->signaler;
-
 		INIT_LIST_HEAD(&dep->dfs_link);
 
+		node = dep->signaler;
 		engine = sched_lock_engine(node, engine, &cache);
 		lockdep_assert_held(&engine->timeline.lock);
 
@@ -315,13 +314,20 @@ static void __i915_schedule(struct i915_request *rq,
 void i915_schedule(struct i915_request *rq, const struct i915_sched_attr *attr)
 {
 	spin_lock_irq(&schedule_lock);
-	__i915_schedule(rq, attr);
+	__i915_schedule(&rq->sched, attr);
 	spin_unlock_irq(&schedule_lock);
 }
 
+static void __bump_priority(struct i915_sched_node *node, unsigned int bump)
+{
+	struct i915_sched_attr attr = node->attr;
+
+	attr.priority |= bump;
+	__i915_schedule(node, &attr);
+}
+
 void i915_schedule_bump_priority(struct i915_request *rq, unsigned int bump)
 {
-	struct i915_sched_attr attr;
 	unsigned long flags;
 
 	GEM_BUG_ON(bump & ~I915_PRIORITY_MASK);
@@ -330,11 +336,7 @@ void i915_schedule_bump_priority(struct i915_request *rq, unsigned int bump)
 		return;
 
 	spin_lock_irqsave(&schedule_lock, flags);
-
-	attr = rq->sched.attr;
-	attr.priority |= bump;
-	__i915_schedule(rq, &attr);
-
+	__bump_priority(&rq->sched, bump);
 	spin_unlock_irqrestore(&schedule_lock, flags);
 }