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 <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Carsten Emde <cbe@osadl.org>
Tested-by: Mathias Weber <mathias.weber.mw1@roche.com>
LKML-Reference: <20100120171629.734886007@linutronix.de>

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);