drm/amdgpu/vcn: adjust workload profile handling

No need to make the workload profile setup dependent
on the results of cancelling the delayed work thread.
We have all of the necessary checking in place for the
workload profile reference counting, so separate the
two.  As it is now, we can theoretically end up with
the call from begin_use happening while the worker
thread is executing which would result in the profile
not getting set for that submission.  It should not
affect the reference counting.

v2: bail early if the the profile is already active (Lijo)

Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

2 files changed, 36 insertions, 20 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
index 6b410e601bb6..1991dd3d1056 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
@@ -460,18 +460,26 @@ void amdgpu_vcn_ring_begin_use(struct amdgpu_ring *ring)
 
 	atomic_inc(&vcn_inst->total_submission_cnt);
 
-	if (!cancel_delayed_work_sync(&vcn_inst->idle_work)) {
-		mutex_lock(&adev->vcn.workload_profile_mutex);
-		if (!adev->vcn.workload_profile_active) {
-			r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
-							    true);
-			if (r)
-				dev_warn(adev->dev, "(%d) failed to switch to video power profile mode\n", r);
-			adev->vcn.workload_profile_active = true;
-		}
-		mutex_unlock(&adev->vcn.workload_profile_mutex);
+	cancel_delayed_work_sync(&vcn_inst->idle_work);
+
+	/* We can safely return early here because we've cancelled the
+	 * the delayed work so there is no one else to set it to false
+	 * and we don't care if someone else sets it to true.
+	 */
+	if (adev->vcn.workload_profile_active)
+		goto pg_lock;
+
+	mutex_lock(&adev->vcn.workload_profile_mutex);
+	if (!adev->vcn.workload_profile_active) {
+		r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
+						    true);
+		if (r)
+			dev_warn(adev->dev, "(%d) failed to switch to video power profile mode\n", r);
+		adev->vcn.workload_profile_active = true;
 	}
+	mutex_unlock(&adev->vcn.workload_profile_mutex);
 
+pg_lock:
 	mutex_lock(&vcn_inst->vcn_pg_lock);
 	vcn_inst->set_pg_state(vcn_inst, AMD_PG_STATE_UNGATE);
 
diff --git a/drivers/gpu/drm/amd/amdgpu/vcn_v2_5.c b/drivers/gpu/drm/amd/amdgpu/vcn_v2_5.c
index b4b8091980ad..d716510b8dd6 100644
--- a/drivers/gpu/drm/amd/amdgpu/vcn_v2_5.c
+++ b/drivers/gpu/drm/amd/amdgpu/vcn_v2_5.c
@@ -169,18 +169,26 @@ static void vcn_v2_5_ring_begin_use(struct amdgpu_ring *ring)
 
 	atomic_inc(&adev->vcn.inst[0].total_submission_cnt);
 
-	if (!cancel_delayed_work_sync(&adev->vcn.inst[0].idle_work)) {
-		mutex_lock(&adev->vcn.workload_profile_mutex);
-		if (!adev->vcn.workload_profile_active) {
-			r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
-							    true);
-			if (r)
-				dev_warn(adev->dev, "(%d) failed to switch to video power profile mode\n", r);
-			adev->vcn.workload_profile_active = true;
-		}
-		mutex_unlock(&adev->vcn.workload_profile_mutex);
+	cancel_delayed_work_sync(&adev->vcn.inst[0].idle_work);
+
+	/* We can safely return early here because we've cancelled the
+	 * the delayed work so there is no one else to set it to false
+	 * and we don't care if someone else sets it to true.
+	 */
+	if (adev->vcn.workload_profile_active)
+		goto pg_lock;
+
+	mutex_lock(&adev->vcn.workload_profile_mutex);
+	if (!adev->vcn.workload_profile_active) {
+		r = amdgpu_dpm_switch_power_profile(adev, PP_SMC_POWER_PROFILE_VIDEO,
+						    true);
+		if (r)
+			dev_warn(adev->dev, "(%d) failed to switch to video power profile mode\n", r);
+		adev->vcn.workload_profile_active = true;
 	}
+	mutex_unlock(&adev->vcn.workload_profile_mutex);
 
+pg_lock:
 	mutex_lock(&adev->vcn.inst[0].vcn_pg_lock);
 	amdgpu_device_ip_set_powergating_state(adev, AMD_IP_BLOCK_TYPE_VCN,
 					       AMD_PG_STATE_UNGATE);