sched: rt-group: make rt groups scheduling configurable

Make the rt group scheduler compile time configurable.
Keep it experimental for now.

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

include/linux/cgroup_subsys.h

@@ -25,7 +25,7 @@ SUBSYS(ns)
 
 /* */
 
-#ifdef CONFIG_FAIR_CGROUP_SCHED
+#ifdef CONFIG_CGROUP_SCHED
 SUBSYS(cpu_cgroup)
 #endif
 

include/linux/sched.h

@@ -590,7 +590,7 @@ struct user_struct {
 	struct hlist_node uidhash_node;
 	uid_t uid;
 
-#ifdef CONFIG_FAIR_USER_SCHED
+#ifdef CONFIG_USER_SCHED
 	struct task_group *tg;
 #ifdef CONFIG_SYSFS
 	struct kobject kobj;
@@ -973,7 +973,7 @@ struct sched_rt_entity {
 	unsigned long timeout;
 	int nr_cpus_allowed;
 
-#ifdef CONFIG_FAIR_GROUP_SCHED
+#ifdef CONFIG_RT_GROUP_SCHED
 	struct sched_rt_entity	*parent;
 	/* rq on which this entity is (to be) queued: */
 	struct rt_rq		*rt_rq;
@@ -2027,19 +2027,22 @@ extern int sched_mc_power_savings, sched_smt_power_savings;
 
 extern void normalize_rt_tasks(void);
 
-#ifdef CONFIG_FAIR_GROUP_SCHED
+#ifdef CONFIG_GROUP_SCHED
 
 extern struct task_group init_task_group;
 
 extern struct task_group *sched_create_group(void);
 extern void sched_destroy_group(struct task_group *tg);
 extern void sched_move_task(struct task_struct *tsk);
+#ifdef CONFIG_FAIR_GROUP_SCHED
 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
 extern unsigned long sched_group_shares(struct task_group *tg);
+#endif
+#ifdef CONFIG_RT_GROUP_SCHED
 extern int sched_group_set_rt_runtime(struct task_group *tg,
 				      long rt_runtime_us);
 extern long sched_group_rt_runtime(struct task_group *tg);
-
+#endif
 #endif
 
 #ifdef CONFIG_TASK_XACCT

init/Kconfig

@@ -311,25 +311,36 @@ config CPUSETS
 
 	  Say N if unsure.
 
-config FAIR_GROUP_SCHED
-	bool "Fair group CPU scheduler"
+config GROUP_SCHED
+	bool "Group CPU scheduler"
 	default y
 	help
 	  This feature lets CPU scheduler recognize task groups and control CPU
 	  bandwidth allocation to such task groups.
 
+config FAIR_GROUP_SCHED
+	bool "Group scheduling for SCHED_OTHER"
+	depends on GROUP_SCHED
+	default y
+
+config RT_GROUP_SCHED
+	bool "Group scheduling for SCHED_RR/FIFO"
+	depends on EXPERIMENTAL
+	depends on GROUP_SCHED
+	default n
+
 choice
-	depends on FAIR_GROUP_SCHED
+	depends on GROUP_SCHED
 	prompt "Basis for grouping tasks"
-	default FAIR_USER_SCHED
+	default USER_SCHED
 
-config FAIR_USER_SCHED
+config USER_SCHED
 	bool "user id"
 	help
 	  This option will choose userid as the basis for grouping
 	  tasks, thus providing equal CPU bandwidth to each user.
 
-config FAIR_CGROUP_SCHED
+config CGROUP_SCHED
 	bool "Control groups"
  	depends on CGROUPS
  	help