media: mediatek: vcodec: making sure queue_work successfully

Putting core work to work queue using queue_work maybe fail, call
queue_work again when the count of core work in work queue is less
than core_list_cnt, making sure all the buffer in core list can be
scheduled.

Fixes: 365e4ba0 ("media: mtk-vcodec: Add work queue for core hardware decode")
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/mediatek/vcodec/vdec_msg_queue.c

@@ -71,6 +71,7 @@ static void vdec_msg_queue_dec(struct vdec_msg_queue *msg_queue, int hardware_in
 int vdec_msg_queue_qbuf(struct vdec_msg_queue_ctx *msg_ctx, struct vdec_lat_buf *buf)
 {
 	struct list_head *head;
+	int status;
 
 	head = vdec_get_buf_list(msg_ctx->hardware_index, buf);
 	if (!head) {
@@ -83,11 +84,17 @@ int vdec_msg_queue_qbuf(struct vdec_msg_queue_ctx *msg_ctx, struct vdec_lat_buf
 	msg_ctx->ready_num++;
 
 	vdec_msg_queue_inc(&buf->ctx->msg_queue, msg_ctx->hardware_index);
-	if (msg_ctx->hardware_index != MTK_VDEC_CORE)
+	if (msg_ctx->hardware_index != MTK_VDEC_CORE) {
 		wake_up_all(&msg_ctx->ready_to_use);
-	else
-		queue_work(buf->ctx->dev->core_workqueue,
+	} else {
+		if (buf->ctx->msg_queue.core_work_cnt <
+			atomic_read(&buf->ctx->msg_queue.core_list_cnt)) {
+			status = queue_work(buf->ctx->dev->core_workqueue,
 					    &buf->ctx->msg_queue.core_work);
+			if (status)
+				buf->ctx->msg_queue.core_work_cnt++;
+		}
+	}
 
 	mtk_v4l2_debug(3, "enqueue buf type: %d addr: 0x%p num: %d",
 		       msg_ctx->hardware_index, buf, msg_ctx->ready_num);
@@ -254,6 +261,7 @@ static void vdec_msg_queue_core_work(struct work_struct *work)
 		container_of(msg_queue, struct mtk_vcodec_ctx, msg_queue);
 	struct mtk_vcodec_dev *dev = ctx->dev;
 	struct vdec_lat_buf *lat_buf;
+	int status;
 
 	lat_buf = vdec_msg_queue_dqbuf(&dev->msg_queue_core_ctx);
 	if (!lat_buf)
@@ -270,11 +278,17 @@ static void vdec_msg_queue_core_work(struct work_struct *work)
 	vdec_msg_queue_qbuf(&ctx->msg_queue.lat_ctx, lat_buf);
 
 	wake_up_all(&ctx->msg_queue.core_dec_done);
-	if (atomic_read(&lat_buf->ctx->msg_queue.core_list_cnt)) {
-		mtk_v4l2_debug(3, "re-schedule to decode for core: %d",
-			       dev->msg_queue_core_ctx.ready_num);
-		queue_work(dev->core_workqueue, &msg_queue->core_work);
+	spin_lock(&dev->msg_queue_core_ctx.ready_lock);
+	lat_buf->ctx->msg_queue.core_work_cnt--;
+
+	if (lat_buf->ctx->msg_queue.core_work_cnt <
+		atomic_read(&lat_buf->ctx->msg_queue.core_list_cnt)) {
+		status = queue_work(lat_buf->ctx->dev->core_workqueue,
+				    &lat_buf->ctx->msg_queue.core_work);
+		if (status)
+			lat_buf->ctx->msg_queue.core_work_cnt++;
 	}
+	spin_unlock(&dev->msg_queue_core_ctx.ready_lock);
 }
 
 int vdec_msg_queue_init(struct vdec_msg_queue *msg_queue,
@@ -289,6 +303,7 @@ int vdec_msg_queue_init(struct vdec_msg_queue *msg_queue,
 		return 0;
 
 	msg_queue->ctx = ctx;
+	msg_queue->core_work_cnt = 0;
 	vdec_msg_queue_init_ctx(&msg_queue->lat_ctx, MTK_VDEC_LAT0);
 	INIT_WORK(&msg_queue->core_work, vdec_msg_queue_core_work);
 

drivers/media/platform/mediatek/vcodec/vdec_msg_queue.h

@@ -77,6 +77,7 @@ struct vdec_lat_buf {
  * @lat_list_cnt: used to record each instance lat list count
  * @core_list_cnt: used to record each instance core list count
  * @core_dec_done: core work queue decode done event
+ * @core_work_cnt: the number of core work in work queue
  */
 struct vdec_msg_queue {
 	struct vdec_lat_buf lat_buf[NUM_BUFFER_COUNT];
@@ -92,6 +93,7 @@ struct vdec_msg_queue {
 	atomic_t lat_list_cnt;
 	atomic_t core_list_cnt;
 	wait_queue_head_t core_dec_done;
+	int core_work_cnt;
 };
 
 /**