[PATCH 3/5] drm/i915/gvt: control the scheduler by timeslice usage

[Ping Gao]

The timeslice usage will determine vGPU whether has chance to
schedule or not in a 100ms time slot.

Signed-off-by: Ping Gao <ping.a.gao at intel.com>
---
 drivers/gpu/drm/i915/gvt/sched_policy.c | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/sched_policy.c b/drivers/gpu/drm/i915/gvt/sched_policy.c
index 71c7913..513714b 100644
--- a/drivers/gpu/drm/i915/gvt/sched_policy.c
+++ b/drivers/gpu/drm/i915/gvt/sched_policy.c
@@ -190,6 +190,7 @@ static inline int gvt_nr_in_runq(struct tbs_sched_data *sched_data)
 }
 
 #define GVT_DEFAULT_TIME_SLICE (1 * HZ / 1000)
+#define vgpu_has_ts_limit(vgpu_data) ((vgpu_data)->ts_alloc < GVT_TS_BALANCE_PERIOD)
 
 static void tbs_sched_func(struct work_struct *work)
 {
@@ -228,11 +229,23 @@ static void tbs_sched_func(struct work_struct *work)
 			continue;
 
 		vgpu_data = container_of(pos, struct tbs_vgpu_data, list);
-		if (!vgpu_has_pending_workload(vgpu_data->vgpu))
-			continue;
 
-		vgpu = vgpu_data->vgpu;
-		break;
+		if (gvt_nr_in_runq(sched_data) == 1) {
+			vgpu = vgpu_data->vgpu;
+			break;
+		}
+		/* no need to check timeslice usage
+		 * if alloced the Max timeslice
+		 */
+		if (!vgpu_has_ts_limit(vgpu_data)) {
+			vgpu = vgpu_data->vgpu;
+			break;
+		}
+		/* allowed to schedule if has time slice left */
+		else if (vgpu_data->ts_usage > 0) {
+			vgpu = vgpu_data->vgpu;
+			break;
+		}
 	}
 
 	if (vgpu) {
-- 
2.7.4