[PATCH 1/2] drm/i915/gvt: support event based scheduling

[Ping Gao]

This patch decouple the time slice caculation and scheduler, let
other event be able to trigger scheduling without impact the
calcuation for QoS.

Signed-off-by: Ping Gao <ping.a.gao at intel.com>
---
 drivers/gpu/drm/i915/gvt/gvt.c          |  4 +++-
 drivers/gpu/drm/i915/gvt/gvt.h          |  3 ++-
 drivers/gpu/drm/i915/gvt/sched_policy.c | 17 +++++++++++------
 3 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c
index 7dea5e5..b429ea2 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.c
+++ b/drivers/gpu/drm/i915/gvt/gvt.c
@@ -147,7 +147,9 @@ static int gvt_service_thread(void *data)
 			mutex_unlock(&gvt->lock);
 		}
 
-		if (test_and_clear_bit(INTEL_GVT_REQUEST_SCHED,
+		if (test_bit(INTEL_GVT_REQUEST_TIME_SCHED,
+				(void *)&gvt->service_request) ||
+			test_bit(INTEL_GVT_REQUEST_EVENT_SCHED,
 					(void *)&gvt->service_request)) {
 			intel_gvt_schedule(gvt);
 		}
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index 930732e..36c849f 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -257,7 +257,8 @@ static inline struct intel_gvt *to_gvt(struct drm_i915_private *i915)
 
 enum {
 	INTEL_GVT_REQUEST_EMULATE_VBLANK = 0,
-	INTEL_GVT_REQUEST_SCHED = 1,
+	INTEL_GVT_REQUEST_TIME_SCHED = 1,
+	INTEL_GVT_REQUEST_EVENT_SCHED = 2,
 };
 
 static inline void intel_gvt_request_service(struct intel_gvt *gvt,
diff --git a/drivers/gpu/drm/i915/gvt/sched_policy.c b/drivers/gpu/drm/i915/gvt/sched_policy.c
index f25ff13..febf560 100644
--- a/drivers/gpu/drm/i915/gvt/sched_policy.c
+++ b/drivers/gpu/drm/i915/gvt/sched_policy.c
@@ -202,11 +202,6 @@ static void tbs_sched_func(struct gvt_sched_data *sched_data)
 	struct intel_gvt_workload_scheduler *scheduler = &gvt->scheduler;
 	struct vgpu_sched_data *vgpu_data;
 	struct intel_vgpu *vgpu = NULL;
-	static uint64_t timer_check;
-
-	if (!(timer_check++ % GVT_TS_BALANCE_PERIOD_MS))
-		gvt_balance_timeslice(sched_data);
-
 	/* no active vgpu or has already had a target */
 	if (list_empty(&sched_data->lru_runq_head) || scheduler->next_vgpu)
 		goto out;
@@ -231,9 +226,19 @@ static void tbs_sched_func(struct gvt_sched_data *sched_data)
 void intel_gvt_schedule(struct intel_gvt *gvt)
 {
 	struct gvt_sched_data *sched_data = gvt->scheduler.sched_data;
+	static uint64_t timer_check;
 
 	mutex_lock(&gvt->lock);
+
+	if (test_and_clear_bit(INTEL_GVT_REQUEST_TIME_SCHED,
+				(void *)&gvt->service_request)) {
+		if (!(timer_check++ % GVT_TS_BALANCE_PERIOD_MS))
+			gvt_balance_timeslice(sched_data);
+	}
+	clear_bit(INTEL_GVT_REQUEST_EVENT_SCHED, (void *)&gvt->service_request);
+
 	tbs_sched_func(sched_data);
+
 	mutex_unlock(&gvt->lock);
 }
 
@@ -243,7 +248,7 @@ static enum hrtimer_restart tbs_timer_fn(struct hrtimer *timer_data)
 
 	data = container_of(timer_data, struct gvt_sched_data, timer);
 
-	intel_gvt_request_service(data->gvt, INTEL_GVT_REQUEST_SCHED);
+	intel_gvt_request_service(data->gvt, INTEL_GVT_REQUEST_TIME_SCHED);
 
 	hrtimer_add_expires_ns(&data->timer, data->period);
 
-- 
2.7.4