sched: Make multiple runqueue task counters 32-bit

Make:

	struct dl_rq::dl_nr_migratory
	struct dl_rq::dl_nr_running

	struct rt_rq::rt_nr_boosted
	struct rt_rq::rt_nr_migratory
	struct rt_rq::rt_nr_total

	struct rq::nr_uninterruptible

32-bit.

If total number of tasks can't exceed 2**32 (and less due to futex pid
limits), then per-runqueue counters can't as well.

This patchset has been sponsored by REX Prefix Eradication Society.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210422200228.1423391-4-adobriyan@gmail.com

kernel/sched/loadavg.c

@@ -81,7 +81,7 @@ long calc_load_fold_active(struct rq *this_rq, long adjust)
 	long nr_active, delta = 0;
 
 	nr_active = this_rq->nr_running - adjust;
-	nr_active += (long)this_rq->nr_uninterruptible;
+	nr_active += (int)this_rq->nr_uninterruptible;
 
 	if (nr_active != this_rq->calc_load_active) {
 		delta = nr_active - this_rq->calc_load_active;

kernel/sched/sched.h

@@ -636,8 +636,8 @@ struct rt_rq {
 	} highest_prio;
 #endif
 #ifdef CONFIG_SMP
-	unsigned long		rt_nr_migratory;
+	unsigned int		rt_nr_migratory;
-	unsigned long		rt_nr_total;
+	unsigned int		rt_nr_total;
 	int			overloaded;
 	struct plist_head	pushable_tasks;
 
@@ -651,7 +651,7 @@ struct rt_rq {
 	raw_spinlock_t		rt_runtime_lock;
 
 #ifdef CONFIG_RT_GROUP_SCHED
-	unsigned long		rt_nr_boosted;
+	unsigned int		rt_nr_boosted;
 
 	struct rq		*rq;
 	struct task_group	*tg;
@@ -668,7 +668,7 @@ struct dl_rq {
 	/* runqueue is an rbtree, ordered by deadline */
 	struct rb_root_cached	root;
 
-	unsigned long		dl_nr_running;
+	unsigned int		dl_nr_running;
 
 #ifdef CONFIG_SMP
 	/*
@@ -682,7 +682,7 @@ struct dl_rq {
 		u64		next;
 	} earliest_dl;
 
-	unsigned long		dl_nr_migratory;
+	unsigned int		dl_nr_migratory;
 	int			overloaded;
 
 	/*
@@ -960,7 +960,7 @@ struct rq {
 	 * one CPU and if it got migrated afterwards it may decrease
 	 * it on another CPU. Always updated under the runqueue lock:
 	 */
-	unsigned long		nr_uninterruptible;
+	unsigned int		nr_uninterruptible;
 
 	struct task_struct __rcu	*curr;
 	struct task_struct	*idle;