sched/deadline: Move some utility functions to deadline.h

Some utility functions on sched_dl_entity can be useful outside of
deadline.c , for instance for modelling, without relying on raw
structure fields.

Move functions like dl_task_of and dl_is_implicit to deadline.h to make
them available outside.

Acked-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/20260330111010.153663-12-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>

Author: glemco

include/linux/sched/deadline.h

@@ -37,4 +37,31 @@ extern void dl_clear_root_domain_cpu(int cpu);
 extern u64 dl_cookie;
 extern bool dl_bw_visited(int cpu, u64 cookie);
 
+static inline bool dl_server(struct sched_dl_entity *dl_se)
+{
+	return dl_se->dl_server;
+}
+
+static inline struct task_struct *dl_task_of(struct sched_dl_entity *dl_se)
+{
+	BUG_ON(dl_server(dl_se));
+	return container_of(dl_se, struct task_struct, dl);
+}
+
+/*
+ * Regarding the deadline, a task with implicit deadline has a relative
+ * deadline == relative period. A task with constrained deadline has a
+ * relative deadline <= relative period.
+ *
+ * We support constrained deadline tasks. However, there are some restrictions
+ * applied only for tasks which do not have an implicit deadline. See
+ * update_dl_entity() to know more about such restrictions.
+ *
+ * The dl_is_implicit() returns true if the task has an implicit deadline.
+ */
+static inline bool dl_is_implicit(struct sched_dl_entity *dl_se)
+{
+	return dl_se->dl_deadline == dl_se->dl_period;
+}
+
 #endif /* _LINUX_SCHED_DEADLINE_H */

kernel/sched/deadline.c

@@ -18,6 +18,7 @@
 
 #include <linux/cpuset.h>
 #include <linux/sched/clock.h>
+#include <linux/sched/deadline.h>
 #include <uapi/linux/sched/types.h>
 #include "sched.h"
 #include "pelt.h"
@@ -57,17 +58,6 @@ static int __init sched_dl_sysctl_init(void)
 late_initcall(sched_dl_sysctl_init);
 #endif /* CONFIG_SYSCTL */
 
-static bool dl_server(struct sched_dl_entity *dl_se)
-{
-	return dl_se->dl_server;
-}
-
-static inline struct task_struct *dl_task_of(struct sched_dl_entity *dl_se)
-{
-	BUG_ON(dl_server(dl_se));
-	return container_of(dl_se, struct task_struct, dl);
-}
-
 static inline struct rq *rq_of_dl_rq(struct dl_rq *dl_rq)
 {
 	return container_of(dl_rq, struct rq, dl);
@@ -990,22 +980,6 @@ update_dl_revised_wakeup(struct sched_dl_entity *dl_se, struct rq *rq)
 	dl_se->runtime = (dl_se->dl_density * laxity) >> BW_SHIFT;
 }
 
-/*
- * Regarding the deadline, a task with implicit deadline has a relative
- * deadline == relative period. A task with constrained deadline has a
- * relative deadline <= relative period.
- *
- * We support constrained deadline tasks. However, there are some restrictions
- * applied only for tasks which do not have an implicit deadline. See
- * update_dl_entity() to know more about such restrictions.
- *
- * The dl_is_implicit() returns true if the task has an implicit deadline.
- */
-static inline bool dl_is_implicit(struct sched_dl_entity *dl_se)
-{
-	return dl_se->dl_deadline == dl_se->dl_period;
-}
-
 /*
  * When a deadline entity is placed in the runqueue, its runtime and deadline
  * might need to be updated. This is done by a CBS wake up rule. There are two