sched: Remove USER_SCHED

Remove the USER_SCHED feature. It has been scheduled to be removed in 2.6.34 as per http://marc.info/?l=linux-kernel&m=125728479022976&w=2 Signed-off-by: Dhaval Giani <[email protected]> Signed-off-by: Peter Zijlstra <[email protected]> LKML-Reference: <1263990378.24844.3.camel@localhost> Signed-off-by: Ingo Molnar <[email protected]>
kawasaki · Jan 21, 2010 · 7c94143 · 7c94143
1 parent 871e35b
commit 7c94143
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diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
@@ -6,21 +6,6 @@ be removed from this file.
 
 ---------------------------
 
-What:	USER_SCHED
-When:	2.6.34
-
-Why:	USER_SCHED was implemented as a proof of concept for group scheduling.
-	The effect of USER_SCHED can already be achieved from userspace with
-	the help of libcgroup. The removal of USER_SCHED will also simplify
-	the scheduler code with the removal of one major ifdef. There are also
-	issues USER_SCHED has with USER_NS. A decision was taken not to fix
-	those and instead remove USER_SCHED. Also new group scheduling
-	features will not be implemented for USER_SCHED.
-
-Who:	Dhaval Giani <[email protected]>
-
----------------------------
-
 What:	PRISM54
 When:	2.6.34
 

diff --git a/include/linux/sched.h b/include/linux/sched.h
@@ -731,14 +731,6 @@ struct user_struct {
 	uid_t uid;
 	struct user_namespace *user_ns;
 
-#ifdef CONFIG_USER_SCHED
-	struct task_group *tg;
-#ifdef CONFIG_SYSFS
-	struct kobject kobj;
-	struct delayed_work work;
-#endif
-#endif
-
 #ifdef CONFIG_PERF_EVENTS
 	atomic_long_t locked_vm;
 #endif
@@ -2502,13 +2494,9 @@ extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
 
 extern void normalize_rt_tasks(void);
 
-#ifdef CONFIG_GROUP_SCHED
+#ifdef CONFIG_CGROUP_SCHED
 
 extern struct task_group init_task_group;
-#ifdef CONFIG_USER_SCHED
-extern struct task_group root_task_group;
-extern void set_tg_uid(struct user_struct *user);
-#endif
 
 extern struct task_group *sched_create_group(struct task_group *parent);
 extern void sched_destroy_group(struct task_group *tg);

diff --git a/init/Kconfig b/init/Kconfig
@@ -435,57 +435,6 @@ config LOG_BUF_SHIFT
 config HAVE_UNSTABLE_SCHED_CLOCK
 	bool
 
-config GROUP_SCHED
-	bool "Group CPU scheduler"
-	depends on EXPERIMENTAL
-	default n
-	help
-	  This feature lets CPU scheduler recognize task groups and control CPU
-	  bandwidth allocation to such task groups.
-	  In order to create a group from arbitrary set of processes, use
-	  CONFIG_CGROUPS. (See Control Group support.)
-
-config FAIR_GROUP_SCHED
-	bool "Group scheduling for SCHED_OTHER"
-	depends on GROUP_SCHED
-	default GROUP_SCHED
-
-config RT_GROUP_SCHED
-	bool "Group scheduling for SCHED_RR/FIFO"
-	depends on EXPERIMENTAL
-	depends on GROUP_SCHED
-	default n
-	help
-	  This feature lets you explicitly allocate real CPU bandwidth
-	  to users or control groups (depending on the "Basis for grouping tasks"
-	  setting below. If enabled, it will also make it impossible to
-	  schedule realtime tasks for non-root users until you allocate
-	  realtime bandwidth for them.
-	  See Documentation/scheduler/sched-rt-group.txt for more information.
-
-choice
-	depends on GROUP_SCHED
-	prompt "Basis for grouping tasks"
-	default 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 CGROUP_SCHED
-	bool "Control groups"
- 	depends on CGROUPS
- 	help
-	  This option allows you to create arbitrary task groups
-	  using the "cgroup" pseudo filesystem and control
-	  the cpu bandwidth allocated to each such task group.
-	  Refer to Documentation/cgroups/cgroups.txt for more
-	  information on "cgroup" pseudo filesystem.
-
-endchoice
-
 menuconfig CGROUPS
 	boolean "Control Group support"
 	help
@@ -606,6 +555,36 @@ config CGROUP_MEM_RES_CTLR_SWAP
 	  Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
 	  size is 4096bytes, 512k per 1Gbytes of swap.
 
+menuconfig CGROUP_SCHED
+	bool "Group CPU scheduler"
+	depends on EXPERIMENTAL && CGROUPS
+	default n
+	help
+	  This feature lets CPU scheduler recognize task groups and control CPU
+	  bandwidth allocation to such task groups. It uses cgroups to group
+	  tasks.
+
+if CGROUP_SCHED
+config FAIR_GROUP_SCHED
+	bool "Group scheduling for SCHED_OTHER"
+	depends on CGROUP_SCHED
+	default CGROUP_SCHED
+
+config RT_GROUP_SCHED
+	bool "Group scheduling for SCHED_RR/FIFO"
+	depends on EXPERIMENTAL
+	depends on CGROUP_SCHED
+	default n
+	help
+	  This feature lets you explicitly allocate real CPU bandwidth
+	  to users or control groups (depending on the "Basis for grouping tasks"
+	  setting below. If enabled, it will also make it impossible to
+	  schedule realtime tasks for non-root users until you allocate
+	  realtime bandwidth for them.
+	  See Documentation/scheduler/sched-rt-group.txt for more information.
+
+endif #CGROUP_SCHED
+
 endif # CGROUPS
 
 config MM_OWNER

diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
@@ -197,16 +197,8 @@ static int __init ksysfs_init(void)
 			goto group_exit;
 	}
 
-	/* create the /sys/kernel/uids/ directory */
-	error = uids_sysfs_init();
-	if (error)
-		goto notes_exit;
-
 	return 0;
 
-notes_exit:
-	if (notes_size > 0)
-		sysfs_remove_bin_file(kernel_kobj, &notes_attr);
 group_exit:
 	sysfs_remove_group(kernel_kobj, &kernel_attr_group);
 kset_exit:

diff --git a/kernel/sched.c b/kernel/sched.c
@@ -233,7 +233,7 @@ static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b)
  */
 static DEFINE_MUTEX(sched_domains_mutex);
 
-#ifdef CONFIG_GROUP_SCHED
+#ifdef CONFIG_CGROUP_SCHED
 
 #include <linux/cgroup.h>
 
@@ -243,13 +243,7 @@ static LIST_HEAD(task_groups);
 
 /* task group related information */
 struct task_group {
-#ifdef CONFIG_CGROUP_SCHED
 	struct cgroup_subsys_state css;
-#endif
-
-#ifdef CONFIG_USER_SCHED
-	uid_t uid;
-#endif
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
 	/* schedulable entities of this group on each cpu */
@@ -274,35 +268,7 @@ struct task_group {
 	struct list_head children;
 };
 
-#ifdef CONFIG_USER_SCHED
-
-/* Helper function to pass uid information to create_sched_user() */
-void set_tg_uid(struct user_struct *user)
-{
-	user->tg->uid = user->uid;
-}
-
-/*
- * Root task group.
- *	Every UID task group (including init_task_group aka UID-0) will
- *	be a child to this group.
- */
-struct task_group root_task_group;
-
-#ifdef CONFIG_FAIR_GROUP_SCHED
-/* Default task group's sched entity on each cpu */
-static DEFINE_PER_CPU(struct sched_entity, init_sched_entity);
-/* Default task group's cfs_rq on each cpu */
-static DEFINE_PER_CPU_SHARED_ALIGNED(struct cfs_rq, init_tg_cfs_rq);
-#endif /* CONFIG_FAIR_GROUP_SCHED */
-
-#ifdef CONFIG_RT_GROUP_SCHED
-static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity);
-static DEFINE_PER_CPU_SHARED_ALIGNED(struct rt_rq, init_rt_rq_var);
-#endif /* CONFIG_RT_GROUP_SCHED */
-#else /* !CONFIG_USER_SCHED */
 #define root_task_group init_task_group
-#endif /* CONFIG_USER_SCHED */
 
 /* task_group_lock serializes add/remove of task groups and also changes to
  * a task group's cpu shares.
@@ -318,11 +284,7 @@ static int root_task_group_empty(void)
 }
 #endif
 
-#ifdef CONFIG_USER_SCHED
-# define INIT_TASK_GROUP_LOAD	(2*NICE_0_LOAD)
-#else /* !CONFIG_USER_SCHED */
 # define INIT_TASK_GROUP_LOAD	NICE_0_LOAD
-#endif /* CONFIG_USER_SCHED */
 
 /*
  * A weight of 0 or 1 can cause arithmetics problems.
@@ -348,11 +310,7 @@ static inline struct task_group *task_group(struct task_struct *p)
 {
 	struct task_group *tg;
 
-#ifdef CONFIG_USER_SCHED
-	rcu_read_lock();
-	tg = __task_cred(p)->user->tg;
-	rcu_read_unlock();
-#elif defined(CONFIG_CGROUP_SCHED)
+#ifdef CONFIG_CGROUP_SCHED
 	tg = container_of(task_subsys_state(p, cpu_cgroup_subsys_id),
 				struct task_group, css);
 #else
@@ -383,7 +341,7 @@ static inline struct task_group *task_group(struct task_struct *p)
 	return NULL;
 }
 
-#endif	/* CONFIG_GROUP_SCHED */
+#endif	/* CONFIG_CGROUP_SCHED */
 
 /* CFS-related fields in a runqueue */
 struct cfs_rq {
@@ -7678,9 +7636,6 @@ void __init sched_init(void)
 #ifdef CONFIG_RT_GROUP_SCHED
 	alloc_size += 2 * nr_cpu_ids * sizeof(void **);
 #endif
-#ifdef CONFIG_USER_SCHED
-	alloc_size *= 2;
-#endif
 #ifdef CONFIG_CPUMASK_OFFSTACK
 	alloc_size += num_possible_cpus() * cpumask_size();
 #endif
@@ -7694,13 +7649,6 @@ void __init sched_init(void)
 		init_task_group.cfs_rq = (struct cfs_rq **)ptr;
 		ptr += nr_cpu_ids * sizeof(void **);
 
-#ifdef CONFIG_USER_SCHED
-		root_task_group.se = (struct sched_entity **)ptr;
-		ptr += nr_cpu_ids * sizeof(void **);
-
-		root_task_group.cfs_rq = (struct cfs_rq **)ptr;
-		ptr += nr_cpu_ids * sizeof(void **);
-#endif /* CONFIG_USER_SCHED */
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 #ifdef CONFIG_RT_GROUP_SCHED
 		init_task_group.rt_se = (struct sched_rt_entity **)ptr;
@@ -7709,13 +7657,6 @@ void __init sched_init(void)
 		init_task_group.rt_rq = (struct rt_rq **)ptr;
 		ptr += nr_cpu_ids * sizeof(void **);
 
-#ifdef CONFIG_USER_SCHED
-		root_task_group.rt_se = (struct sched_rt_entity **)ptr;
-		ptr += nr_cpu_ids * sizeof(void **);
-
-		root_task_group.rt_rq = (struct rt_rq **)ptr;
-		ptr += nr_cpu_ids * sizeof(void **);
-#endif /* CONFIG_USER_SCHED */
 #endif /* CONFIG_RT_GROUP_SCHED */
 #ifdef CONFIG_CPUMASK_OFFSTACK
 		for_each_possible_cpu(i) {
@@ -7735,22 +7676,13 @@ void __init sched_init(void)
 #ifdef CONFIG_RT_GROUP_SCHED
 	init_rt_bandwidth(&init_task_group.rt_bandwidth,
 			global_rt_period(), global_rt_runtime());
-#ifdef CONFIG_USER_SCHED
-	init_rt_bandwidth(&root_task_group.rt_bandwidth,
-			global_rt_period(), RUNTIME_INF);
-#endif /* CONFIG_USER_SCHED */
 #endif /* CONFIG_RT_GROUP_SCHED */
 
-#ifdef CONFIG_GROUP_SCHED
+#ifdef CONFIG_CGROUP_SCHED
 	list_add(&init_task_group.list, &task_groups);
 	INIT_LIST_HEAD(&init_task_group.children);
 
-#ifdef CONFIG_USER_SCHED
-	INIT_LIST_HEAD(&root_task_group.children);
-	init_task_group.parent = &root_task_group;
-	list_add(&init_task_group.siblings, &root_task_group.children);
-#endif /* CONFIG_USER_SCHED */
-#endif /* CONFIG_GROUP_SCHED */
+#endif /* CONFIG_CGROUP_SCHED */
 
 #if defined CONFIG_FAIR_GROUP_SCHED && defined CONFIG_SMP
 	update_shares_data = __alloc_percpu(nr_cpu_ids * sizeof(unsigned long),
@@ -7790,25 +7722,6 @@ void __init sched_init(void)
 		 * directly in rq->cfs (i.e init_task_group->se[] = NULL).
 		 */
 		init_tg_cfs_entry(&init_task_group, &rq->cfs, NULL, i, 1, NULL);
-#elif defined CONFIG_USER_SCHED
-		root_task_group.shares = NICE_0_LOAD;
-		init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, 0, NULL);
-		/*
-		 * In case of task-groups formed thr' the user id of tasks,
-		 * init_task_group represents tasks belonging to root user.
-		 * Hence it forms a sibling of all subsequent groups formed.
-		 * In this case, init_task_group gets only a fraction of overall
-		 * system cpu resource, based on the weight assigned to root
-		 * user's cpu share (INIT_TASK_GROUP_LOAD). This is accomplished
-		 * by letting tasks of init_task_group sit in a separate cfs_rq
-		 * (init_tg_cfs_rq) and having one entity represent this group of
-		 * tasks in rq->cfs (i.e init_task_group->se[] != NULL).
-		 */
-		init_tg_cfs_entry(&init_task_group,
-				&per_cpu(init_tg_cfs_rq, i),
-				&per_cpu(init_sched_entity, i), i, 1,
-				root_task_group.se[i]);
-
 #endif
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 
@@ -7817,12 +7730,6 @@ void __init sched_init(void)
 		INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
 #ifdef CONFIG_CGROUP_SCHED
 		init_tg_rt_entry(&init_task_group, &rq->rt, NULL, i, 1, NULL);
-#elif defined CONFIG_USER_SCHED
-		init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, 0, NULL);
-		init_tg_rt_entry(&init_task_group,
-				&per_cpu(init_rt_rq_var, i),
-				&per_cpu(init_sched_rt_entity, i), i, 1,
-				root_task_group.rt_se[i]);
 #endif
 #endif
 
@@ -8218,7 +8125,7 @@ static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
 }
 #endif /* CONFIG_RT_GROUP_SCHED */
 
-#ifdef CONFIG_GROUP_SCHED
+#ifdef CONFIG_CGROUP_SCHED
 static void free_sched_group(struct task_group *tg)
 {
 	free_fair_sched_group(tg);
@@ -8327,7 +8234,7 @@ void sched_move_task(struct task_struct *tsk)
 
 	task_rq_unlock(rq, &flags);
 }
-#endif /* CONFIG_GROUP_SCHED */
+#endif /* CONFIG_CGROUP_SCHED */
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
 static void __set_se_shares(struct sched_entity *se, unsigned long shares)
@@ -8469,13 +8376,6 @@ static int tg_schedulable(struct task_group *tg, void *data)
 		runtime = d->rt_runtime;
 	}
 
-#ifdef CONFIG_USER_SCHED
-	if (tg == &root_task_group) {
-		period = global_rt_period();
-		runtime = global_rt_runtime();
-	}
-#endif
-
 	/*
 	 * Cannot have more runtime than the period.
 	 */