disp: rotator: set priority for rotator threads

Set the rotator threads priority (commit and
done) to RT.

Change-Id: Ia2db4a86efe1d3ca990cade8424a5c72b3d4595b
Signed-off-by: Gaurav LNU <[email protected]>
Signed-off-by: Vinod Polimera <[email protected]>

rotator/sde_rotator_core.c

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (c) 2021-2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2021-2024 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2015-2020, The Linux Foundation. All rights reserved.
  */
 
@@ -1052,6 +1052,20 @@ static void sde_rotator_put_hw_resource(struct sde_rot_queue *queue,
 			entry->item.session_id, entry->item.sequence_id);
 }
 
+static void rotator_thread_priority_worker(struct kthread_work *work)
+{
+	int ret = 0;
+	struct sched_param param = { 0 };
+	struct task_struct *task = current->group_leader;
+
+	param.sched_priority = 5;
+	ret = sched_setscheduler(task, SCHED_FIFO, &param);
+	if (ret)
+		SDEROT_ERR(
+			"pid:%d name:%s priority update failed %d\n",
+			current->tgid, task->comm, ret);
+}
+
 /*
  * caller will need to call sde_rotator_deinit_queue when
  * the function returns error
@@ -1060,8 +1074,6 @@ static int sde_rotator_init_queue(struct sde_rot_mgr *mgr)
 {
 	int i, size, ret = 0;
 	char name[32];
-	struct sched_param param = { .sched_priority = 5 };
-
 	size = sizeof(struct sde_rot_queue) * mgr->queue_count;
 	mgr->commitq = devm_kzalloc(mgr->device, size, GFP_KERNEL);
 	if (!mgr->commitq)
@@ -1074,21 +1086,16 @@ static int sde_rotator_init_queue(struct sde_rot_mgr *mgr)
 		kthread_init_worker(&mgr->commitq[i].rot_kw);
 		mgr->commitq[i].rot_thread = kthread_run(kthread_worker_fn,
 				&mgr->commitq[i].rot_kw, name);
+		kthread_init_work(&mgr->thread_priority_work,
+				rotator_thread_priority_worker);
+		kthread_queue_work(&mgr->commitq[i].rot_kw,
+				&mgr->thread_priority_work);
+		kthread_flush_work(&mgr->thread_priority_work);
 		if (IS_ERR(mgr->commitq[i].rot_thread)) {
 			ret = -EPERM;
 			mgr->commitq[i].rot_thread = NULL;
 			break;
 		}
-
-		ret = sched_setscheduler(mgr->commitq[i].rot_thread,
-			SCHED_FIFO, &param);
-		if (ret) {
-			SDEROT_ERR(
-				"failed to set kthread priority for commitq %d\n",
-				ret);
-			break;
-		}
-
 		/* timeline not used */
 		mgr->commitq[i].timeline = NULL;
 	}
@@ -1105,21 +1112,16 @@ static int sde_rotator_init_queue(struct sde_rot_mgr *mgr)
 		kthread_init_worker(&mgr->doneq[i].rot_kw);
 		mgr->doneq[i].rot_thread = kthread_run(kthread_worker_fn,
 				&mgr->doneq[i].rot_kw, name);
+		kthread_init_work(&mgr->thread_priority_work,
+				rotator_thread_priority_worker);
+		kthread_queue_work(&mgr->commitq[i].rot_kw,
+				&mgr->thread_priority_work);
+		kthread_flush_work(&mgr->thread_priority_work);
 		if (IS_ERR(mgr->doneq[i].rot_thread)) {
 			ret = -EPERM;
 			mgr->doneq[i].rot_thread = NULL;
 			break;
 		}
-
-		ret = sched_setscheduler(mgr->doneq[i].rot_thread,
-			SCHED_FIFO, &param);
-		if (ret) {
-			SDEROT_ERR(
-				"failed to set kthread priority for doneq %d\n",
-				ret);
-			break;
-		}
-
 		/* timeline not used */
 		mgr->doneq[i].timeline = NULL;
 	}

rotator/sde_rotator_core.h

@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
+ * Copyright (c) 2023-2024 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2015-2019, The Linux Foundation. All rights reserved.
  */
 
@@ -444,6 +445,7 @@ struct sde_rot_mgr {
 	atomic_t device_suspended;
 	struct platform_device *pdev;
 	struct device *device;
+	struct kthread_work thread_priority_work;
 
 	/*
 	 * Managing rotation queues, depends on