sched/fair: Make per-cpu cpumasks static

The load_balance_mask and select_rq_mask percpu variables are only used in
kernel/sched/fair.c.

Make them static and move their allocation into init_sched_fair_class().

Replace kzalloc_node() with zalloc_cpumask_var_node() to get rid of the
CONFIG_CPUMASK_OFFSTACK #ifdef and to align with per-cpu cpumask
allocation for RT (local_cpu_mask in init_sched_rt_class()) and DL
class (local_cpu_mask_dl in init_sched_dl_class()).

[ mingo: Tidied up changelog & touched up the code. ]

Signed-off-by: Bing Huang <huangbing@kylinos.cn>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20220722213609.3901-1-huangbing775@126.com

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 6785e3b..64c0899 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -9563,9 +9563,6 @@ LIST_HEAD(task_groups);
 static struct kmem_cache *task_group_cache __read_mostly;
 #endif
 
-DECLARE_PER_CPU(cpumask_var_t, load_balance_mask);
-DECLARE_PER_CPU(cpumask_var_t, select_rq_mask);
-
 void __init sched_init(void)
 {
        unsigned long ptr = 0;
@@ -9609,14 +9606,6 @@ void __init sched_init(void)
 
 #endif /* CONFIG_RT_GROUP_SCHED */
        }
-#ifdef CONFIG_CPUMASK_OFFSTACK
-       for_each_possible_cpu(i) {
-               per_cpu(load_balance_mask, i) = (cpumask_var_t)kzalloc_node(
-                       cpumask_size(), GFP_KERNEL, cpu_to_node(i));
-               per_cpu(select_rq_mask, i) = (cpumask_var_t)kzalloc_node(
-                       cpumask_size(), GFP_KERNEL, cpu_to_node(i));
-       }
-#endif /* CONFIG_CPUMASK_OFFSTACK */
 
        init_rt_bandwidth(&def_rt_bandwidth, global_rt_period(), global_rt_runtime());
 

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index d22c5e8..da38865 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5893,8 +5893,8 @@ dequeue_throttle:
 #ifdef CONFIG_SMP
 
 /* Working cpumask for: load_balance, load_balance_newidle. */
-DEFINE_PER_CPU(cpumask_var_t, load_balance_mask);
-DEFINE_PER_CPU(cpumask_var_t, select_rq_mask);
+static DEFINE_PER_CPU(cpumask_var_t, load_balance_mask);
+static DEFINE_PER_CPU(cpumask_var_t, select_rq_mask);
 
 #ifdef CONFIG_NO_HZ_COMMON
 
@@ -12074,6 +12074,13 @@ void show_numa_stats(struct task_struct *p, struct seq_file *m)
 __init void init_sched_fair_class(void)
 {
 #ifdef CONFIG_SMP
+       int i;
+
+       for_each_possible_cpu(i) {
+               zalloc_cpumask_var_node(&per_cpu(load_balance_mask, i), GFP_KERNEL, cpu_to_node(i));
+               zalloc_cpumask_var_node(&per_cpu(select_rq_mask,    i), GFP_KERNEL, cpu_to_node(i));
+       }
+
        open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
 
 #ifdef CONFIG_NO_HZ_COMMON