diff mbox

drm/i915/execlists: Avoid kicking the submission too early for rescheduling

Message ID 20180324120902.26104-1-chris@chris-wilson.co.uk (mailing list archive)
State New, archived
Headers show

Commit Message

Chris Wilson March 24, 2018, 12:09 p.m. UTC
If the request is still waiting on external fences, it has not yet been
submitted to the HW queue and so we can forgo kicking the submission
tasklet when re-evaluating its priority.

This should have no impact other than reducing the number of tasklet
wakeups under signal heavy workloads (e.g. switching between engines).

References: f6322eddaff7 ("drm/i915/preemption: Allow preemption between submission ports")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: MichaƂ Winiarski <michal.winiarski@intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
---
 drivers/gpu/drm/i915/intel_lrc.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index b4ab06b05e58..08d8ac9d1f8f 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1051,12 +1051,16 @@  static void queue_request(struct intel_engine_cs *engine,
 	list_add_tail(&pt->link, &lookup_priolist(engine, pt, prio)->requests);
 }
 
-static void submit_queue(struct intel_engine_cs *engine, int prio)
+static void __submit_queue(struct intel_engine_cs *engine, int prio)
 {
-	if (prio > engine->execlists.queue_priority) {
 		engine->execlists.queue_priority = prio;
 		tasklet_hi_schedule(&engine->execlists.tasklet);
-	}
+}
+
+static void submit_queue(struct intel_engine_cs *engine, int prio)
+{
+	if (prio > engine->execlists.queue_priority)
+		__submit_queue(engine, prio);
 }
 
 static void execlists_submit_request(struct i915_request *request)
@@ -1189,7 +1193,14 @@  static void execlists_schedule(struct i915_request *request, int prio)
 			__list_del_entry(&pt->link);
 			queue_request(engine, pt, prio);
 		}
-		submit_queue(engine, prio);
+
+		if (prio > engine->execlists.queue_priority) {
+			struct i915_request *rq =
+				container_of(pt, typeof(*rq), priotree);
+
+			if (i915_sw_fence_done(&rq->submit))
+				__submit_queue(engine, prio);
+		}
 	}
 
 	spin_unlock_irq(&engine->timeline->lock);