sched: Extend enqueue_task to allow head queueing

The ability of enqueueing a task to the head of a SCHED_FIFO priority
list is required to fix some violations of POSIX scheduling policy.

Extend the related functions with a "head" argument.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Tested-by: Carsten Emde <[email protected]>
Tested-by: Mathias Weber <[email protected]>
LKML-Reference: <[email protected]>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 8b079735ae5f..b35c0c7130c8 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1067,7 +1067,8 @@ struct sched_domain;
 struct sched_class {
 	const struct sched_class *next;
 
-	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
+	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup,
+			      bool head);
 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
 	void (*yield_task) (struct rq *rq);