drm/i915/gt: Include a few tracek for timeslicing

Add a few telltales to see when timeslicing is being enabled.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200331120502.14713-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/gt/intel_lrc.c

@@ -1814,16 +1814,25 @@ active_timeslice(const struct intel_engine_cs *engine)
 
 static void set_timeslice(struct intel_engine_cs *engine)
 {
+	unsigned long duration;
+
 	if (!intel_engine_has_timeslices(engine))
 		return;
 
-	set_timer_ms(&engine->execlists.timer, active_timeslice(engine));
+	duration = active_timeslice(engine);
+	ENGINE_TRACE(engine, "bump timeslicing, interval:%lu", duration);
+
+	set_timer_ms(&engine->execlists.timer, duration);
 }
 
 static void start_timeslice(struct intel_engine_cs *engine)
 {
 	struct intel_engine_execlists *execlists = &engine->execlists;
-	int prio = queue_prio(execlists);
+	const int prio = queue_prio(execlists);
+	unsigned long duration;
+
+	if (!intel_engine_has_timeslices(engine))
+		return;
 
 	WRITE_ONCE(execlists->switch_priority_hint, prio);
 	if (prio == INT_MIN)
@@ -1832,7 +1841,12 @@ static void start_timeslice(struct intel_engine_cs *engine)
 	if (timer_pending(&execlists->timer))
 		return;
 
-	set_timer_ms(&execlists->timer, timeslice(engine));
+	duration = timeslice(engine);
+	ENGINE_TRACE(engine,
+		     "start timeslicing, prio:%d, interval:%lu",
+		     prio, duration);
+
+	set_timer_ms(&execlists->timer, duration);
 }
 
 static void record_preemption(struct intel_engine_execlists *execlists)

drivers/gpu/drm/i915/i915_scheduler.c

@@ -209,6 +209,12 @@ static void kick_submission(struct intel_engine_cs *engine,
 	if (!inflight)
 		goto unlock;
 
+	ENGINE_TRACE(engine,
+		     "bumping queue-priority-hint:%d for rq:%llx:%lld, inflight:%llx:%lld prio %d\n",
+		     prio,
+		     rq->fence.context, rq->fence.seqno,
+		     inflight->fence.context, inflight->fence.seqno,
+		     inflight->sched.attr.priority);
 	engine->execlists.queue_priority_hint = prio;
 
 	/*