sched: rt time limit

Very simple time limit on the realtime scheduling classes.
Allow the rq's realtime class to consume sched_rt_ratio of every
sched_rt_period slice. If the class exceeds this quota the fair class
will preempt the realtime class.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 17 insertions, 1 deletions

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 96f31c1bc4f0..3afbd25f43eb 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -306,7 +306,23 @@ static struct ctl_table kern_table[] = {
                 .procname       = "sched_nr_migrate",
                 .data           = &sysctl_sched_nr_migrate,
                 .maxlen         = sizeof(unsigned int),
-                .mode           = 644,
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "sched_rt_period_ms",
+                .data           = &sysctl_sched_rt_period,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "sched_rt_ratio",
+                .data           = &sysctl_sched_rt_ratio,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
                 .proc_handler   = &proc_dointvec,
         },
 #if defined(CONFIG_FAIR_GROUP_SCHED) && defined(CONFIG_SMP)