drm/i915/gvt: Support event based scheduling

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

v2: add only one new enum definition.
v3: fix typo.

Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

3 files changed, 18 insertions, 6 deletions

diff --git a/drivers/gpu/drm/i915/gvt/gvt.c b/drivers/gpu/drm/i915/gvt/gvt.c
index 20329171e4ab..c27c6838eaca 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_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 d3b4d42063da..8fd40f55caf1 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -256,7 +256,12 @@ static inline struct intel_gvt *to_gvt(struct drm_i915_private *i915)
 
 enum {
         INTEL_GVT_REQUEST_EMULATE_VBLANK = 0,
+
+        /* Scheduling trigger by timer */
         INTEL_GVT_REQUEST_SCHED = 1,
+
+        /* Scheduling trigger by event */
+        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 f642a3f0cfa0..6f2073d74de2 100644
--- a/drivers/gpu/drm/i915/gvt/sched_policy.c
+++ b/drivers/gpu/drm/i915/gvt/sched_policy.c
@@ -198,11 +198,6 @@ 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;
@@ -227,9 +222,19 @@ out:
 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_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);
 }