v4.19.13 snapshot.
diff --git a/include/linux/sched/deadline.h b/include/linux/sched/deadline.h
new file mode 100644
index 0000000..0cb0343
--- /dev/null
+++ b/include/linux/sched/deadline.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * SCHED_DEADLINE tasks has negative priorities, reflecting
+ * the fact that any of them has higher prio than RT and
+ * NORMAL/BATCH tasks.
+ */
+
+#define MAX_DL_PRIO 0
+
+static inline int dl_prio(int prio)
+{
+ if (unlikely(prio < MAX_DL_PRIO))
+ return 1;
+ return 0;
+}
+
+static inline int dl_task(struct task_struct *p)
+{
+ return dl_prio(p->prio);
+}
+
+static inline bool dl_time_before(u64 a, u64 b)
+{
+ return (s64)(a - b) < 0;
+}