[PATCH 2/2] drm/i915/gvt: Kick scheduler when new workload queued

[changbin.du at intel.com]

From: Changbin Du <changbin.du at intel.com>

The current schedule policy rely on a 1ms timer to execute workload. This
can introduce maximum 1ms unnecessary latency. This is especially bad for
small media workloads.

And I don't think we need this timer for QoS, but the change is not simply
remove the code. So I made a new API intel_gvt_kick_schedule() for future
change.

Signed-off-by: Changbin Du <changbin.du at intel.com>
---
 drivers/gpu/drm/i915/gvt/sched_policy.c | 5 +++++
 drivers/gpu/drm/i915/gvt/sched_policy.h | 2 ++
 drivers/gpu/drm/i915/gvt/scheduler.c    | 1 +
 3 files changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/i915/gvt/sched_policy.c b/drivers/gpu/drm/i915/gvt/sched_policy.c
index 03532df..eea1a2f 100644
--- a/drivers/gpu/drm/i915/gvt/sched_policy.c
+++ b/drivers/gpu/drm/i915/gvt/sched_policy.c
@@ -372,6 +372,11 @@ void intel_vgpu_start_schedule(struct intel_vgpu *vgpu)
 	vgpu->gvt->scheduler.sched_ops->start_schedule(vgpu);
 }
 
+void intel_gvt_kick_schedule(struct intel_gvt *gvt)
+{
+	intel_gvt_request_service(gvt, INTEL_GVT_REQUEST_EVENT_SCHED);
+}
+
 void intel_vgpu_stop_schedule(struct intel_vgpu *vgpu)
 {
 	struct intel_gvt_workload_scheduler *scheduler =
diff --git a/drivers/gpu/drm/i915/gvt/sched_policy.h b/drivers/gpu/drm/i915/gvt/sched_policy.h
index ba00a5f..7b59e3e 100644
--- a/drivers/gpu/drm/i915/gvt/sched_policy.h
+++ b/drivers/gpu/drm/i915/gvt/sched_policy.h
@@ -57,4 +57,6 @@ void intel_vgpu_start_schedule(struct intel_vgpu *vgpu);
 
 void intel_vgpu_stop_schedule(struct intel_vgpu *vgpu);
 
+void intel_gvt_kick_schedule(struct intel_gvt *gvt);
+
 #endif
diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c
index 4d895b55..65918a3 100644
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -1338,5 +1338,6 @@ void intel_vgpu_queue_workload(struct intel_vgpu_workload *workload)
 {
 	list_add_tail(&workload->list,
 		workload_q_head(workload->vgpu, workload->ring_id));
+	intel_gvt_kick_schedule(workload->vgpu->gvt);
 	wake_up(&workload->vgpu->gvt->scheduler.waitq[workload->ring_id]);
 }
-- 
2.7.4