From 3546d2ead1e44e7bbae3615245ba11e98d7baf46 Mon Sep 17 00:00:00 2001
From: Clark Williams <williams@redhat.com>
Date: Thu, 7 Feb 2013 09:47:04 -0600
Subject: [PATCH] --- yaml --- r: 350143 b: refs/heads/master c:
 ce0dbbbb30aee6a835511d5be446462388ba9eee h: refs/heads/master i:   350141:
 f627f7fe7424e04bdda9691fd3886fe8fc05391e   350139:
 414d94af5248d57c91136568938b57da76666176   350135:
 fc0c46953713ba14ac97589cacf06e40d84a32e7   350127:
 4f15255b18867c395e958516d614f755e0b68a3b   350111:
 5237ada4fe6dea492c3dafa7522ab836b270643c   350079:
 d406930bb4190f5ee38efa5f5aa031e74c5c6b9c v: v3

---
 [refs]                             |  2 +-
 trunk/include/linux/sched/sysctl.h | 15 ++++++++++++++-
 trunk/kernel/sched/core.c          | 19 +++++++++++++++++++
 trunk/kernel/sched/rt.c            |  6 ++++--
 trunk/kernel/sysctl.c              |  7 +++++++
 5 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 8a5f792b1f32..aed264bcd05c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cf4aebc292fac7f34f8345664320e9d4a42ca76c
+refs/heads/master: ce0dbbbb30aee6a835511d5be446462388ba9eee
diff --git a/trunk/include/linux/sched/sysctl.h b/trunk/include/linux/sched/sysctl.h
index bac914e458ca..d2bb0ae979d0 100644
--- a/trunk/include/linux/sched/sysctl.h
+++ b/trunk/include/linux/sched/sysctl.h
@@ -73,6 +73,13 @@ static inline unsigned int get_sysctl_timer_migration(void)
 	return 1;
 }
 #endif
+
+/*
+ *  control realtime throttling:
+ *
+ *  /proc/sys/kernel/sched_rt_period_us
+ *  /proc/sys/kernel/sched_rt_runtime_us
+ */
 extern unsigned int sysctl_sched_rt_period;
 extern int sysctl_sched_rt_runtime;
 
@@ -90,7 +97,13 @@ extern unsigned int sysctl_sched_autogroup_enabled;
  */
 #define RR_TIMESLICE		(100 * HZ / 1000)
 
-int sched_rt_handler(struct ctl_table *table, int write,
+extern int sched_rr_timeslice;
+
+extern int sched_rr_handler(struct ctl_table *table, int write,
+		void __user *buffer, size_t *lenp,
+		loff_t *ppos);
+
+extern int sched_rt_handler(struct ctl_table *table, int write,
 		void __user *buffer, size_t *lenp,
 		loff_t *ppos);
 
diff --git a/trunk/kernel/sched/core.c b/trunk/kernel/sched/core.c
index 1dff78a9e2ab..4a88f1d51563 100644
--- a/trunk/kernel/sched/core.c
+++ b/trunk/kernel/sched/core.c
@@ -7509,6 +7509,25 @@ static int sched_rt_global_constraints(void)
 }
 #endif /* CONFIG_RT_GROUP_SCHED */
 
+int sched_rr_handler(struct ctl_table *table, int write,
+		void __user *buffer, size_t *lenp,
+		loff_t *ppos)
+{
+	int ret;
+	static DEFINE_MUTEX(mutex);
+
+	mutex_lock(&mutex);
+	ret = proc_dointvec(table, write, buffer, lenp, ppos);
+	/* make sure that internally we keep jiffies */
+	/* also, writing zero resets timeslice to default */
+	if (!ret && write) {
+		sched_rr_timeslice = sched_rr_timeslice <= 0 ?
+			RR_TIMESLICE : msecs_to_jiffies(sched_rr_timeslice);
+	}
+	mutex_unlock(&mutex);
+	return ret;
+}
+
 int sched_rt_handler(struct ctl_table *table, int write,
 		void __user *buffer, size_t *lenp,
 		loff_t *ppos)
diff --git a/trunk/kernel/sched/rt.c b/trunk/kernel/sched/rt.c
index c25de141c576..fb0f77e402b6 100644
--- a/trunk/kernel/sched/rt.c
+++ b/trunk/kernel/sched/rt.c
@@ -7,6 +7,8 @@
 
 #include <linux/slab.h>
 
+int sched_rr_timeslice = RR_TIMESLICE;
+
 static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
 
 struct rt_bandwidth def_rt_bandwidth;
@@ -2016,7 +2018,7 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
 	if (--p->rt.time_slice)
 		return;
 
-	p->rt.time_slice = RR_TIMESLICE;
+	p->rt.time_slice = sched_rr_timeslice;
 
 	/*
 	 * Requeue to the end of queue if we (and all of our ancestors) are the
@@ -2047,7 +2049,7 @@ static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
 	 * Time slice is 0 for SCHED_FIFO tasks
 	 */
 	if (task->policy == SCHED_RR)
-		return RR_TIMESLICE;
+		return sched_rr_timeslice;
 	else
 		return 0;
 }
diff --git a/trunk/kernel/sysctl.c b/trunk/kernel/sysctl.c
index 7357e23aaf68..4fc9be955c71 100644
--- a/trunk/kernel/sysctl.c
+++ b/trunk/kernel/sysctl.c
@@ -404,6 +404,13 @@ static struct ctl_table kern_table[] = {
 		.mode		= 0644,
 		.proc_handler	= sched_rt_handler,
 	},
+	{
+		.procname	= "sched_rr_timeslice_ms",
+		.data		= &sched_rr_timeslice,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= sched_rr_handler,
+	},
 #ifdef CONFIG_SCHED_AUTOGROUP
 	{
 		.procname	= "sched_autogroup_enabled",