sched: add CONFIG_SMP consistency

a patch from Henrik Austad did this:

>> Do not declare select_task_rq as part of sched_class when CONFIG_SMP is
>> not set.

Peter observed:

> While a proper cleanup, could you do it by re-arranging the methods so
> as to not create an additional ifdef?

Do not declare select_task_rq and some other methods as part of sched_class
when CONFIG_SMP is not set.

Also gather those methods to avoid CONFIG_SMP mess.

Idea-by: Henrik Austad <henrik.austad@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Henrik Austad <henrik@austad.us>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 13 insertions, 14 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 4f59c8e8597d..c05b45faef18 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -897,7 +897,6 @@ struct sched_class {
         void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
         void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
         void (*yield_task) (struct rq *rq);
-        int  (*select_task_rq)(struct task_struct *p, int sync);
 
         void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int sync);
 
@@ -905,6 +904,8 @@ struct sched_class {
         void (*put_prev_task) (struct rq *rq, struct task_struct *p);
 
 #ifdef CONFIG_SMP
+        int  (*select_task_rq)(struct task_struct *p, int sync);
+
         unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
                         struct rq *busiest, unsigned long max_load_move,
                         struct sched_domain *sd, enum cpu_idle_type idle,
@@ -916,16 +917,17 @@ struct sched_class {
         void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
         void (*post_schedule) (struct rq *this_rq);
         void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
-#endif
 
-        void (*set_curr_task) (struct rq *rq);
-        void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
-        void (*task_new) (struct rq *rq, struct task_struct *p);
         void (*set_cpus_allowed)(struct task_struct *p,
                                  const cpumask_t *newmask);
 
         void (*rq_online)(struct rq *rq);
         void (*rq_offline)(struct rq *rq);
+#endif
+
+        void (*set_curr_task) (struct rq *rq);
+        void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
+        void (*task_new) (struct rq *rq, struct task_struct *p);
 
         void (*switched_from) (struct rq *this_rq, struct task_struct *task,
                                int running);
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index a0aa38b10fdd..8de48a5da354 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1593,9 +1593,6 @@ static const struct sched_class fair_sched_class = {
         .enqueue_task           = enqueue_task_fair,
         .dequeue_task           = dequeue_task_fair,
         .yield_task             = yield_task_fair,
-#ifdef CONFIG_SMP
-        .select_task_rq         = select_task_rq_fair,
-#endif /* CONFIG_SMP */
 
         .check_preempt_curr     = check_preempt_wakeup,
 
@@ -1603,6 +1600,8 @@ static const struct sched_class fair_sched_class = {
         .put_prev_task          = put_prev_task_fair,
 
 #ifdef CONFIG_SMP
+        .select_task_rq         = select_task_rq_fair,
+
         .load_balance           = load_balance_fair,
         .move_one_task          = move_one_task_fair,
 #endif
diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c
index dec4ccabe2f5..8a21a2e28c13 100644
--- a/kernel/sched_idletask.c
+++ b/kernel/sched_idletask.c
@@ -105,9 +105,6 @@ static const struct sched_class idle_sched_class = {
 
         /* dequeue is not valid, we print a debug message there: */
         .dequeue_task           = dequeue_task_idle,
-#ifdef CONFIG_SMP
-        .select_task_rq         = select_task_rq_idle,
-#endif /* CONFIG_SMP */
 
         .check_preempt_curr     = check_preempt_curr_idle,
 
@@ -115,6 +112,8 @@ static const struct sched_class idle_sched_class = {
         .put_prev_task          = put_prev_task_idle,
 
 #ifdef CONFIG_SMP
+        .select_task_rq         = select_task_rq_idle,
+
         .load_balance           = load_balance_idle,
         .move_one_task          = move_one_task_idle,
 #endif
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index cdf5740ab03e..c9aa5bede226 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1502,9 +1502,6 @@ static const struct sched_class rt_sched_class = {
         .enqueue_task           = enqueue_task_rt,
         .dequeue_task           = dequeue_task_rt,
         .yield_task             = yield_task_rt,
-#ifdef CONFIG_SMP
-        .select_task_rq         = select_task_rq_rt,
-#endif /* CONFIG_SMP */
 
         .check_preempt_curr     = check_preempt_curr_rt,
 
@@ -1512,6 +1509,8 @@ static const struct sched_class rt_sched_class = {
         .put_prev_task          = put_prev_task_rt,
 
 #ifdef CONFIG_SMP
+        .select_task_rq         = select_task_rq_rt,
+
         .load_balance           = load_balance_rt,
         .move_one_task          = move_one_task_rt,
         .set_cpus_allowed       = set_cpus_allowed_rt,