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[PATCH v4] sched/fair: Make per-cpu cpumasks static

Bing Huang posted 1 patch 3 years, 10 months ago
There is a newer version of this series
kernel/sched/core.c | 11 -----------
kernel/sched/fair.c | 13 +++++++++++--
2 files changed, 11 insertions(+), 13 deletions(-)
[PATCH v4] sched/fair: Make per-cpu cpumasks static
Posted by Bing Huang 3 years, 10 months ago 
From: Bing Huang <huangbing@kylinos.cn>

load_balance_mask and select_idle_mask are only used in 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()).

Signed-off-by: Bing Huang <huangbing@kylinos.cn>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
---

 v1->v2:
   move load_balance_mask and select_idle_mask allocation from
   sched_init() to init_sched_fair_class()
 v2->v3:
   fixup by Dietmar Eggemann <dietmar.eggemann@arm.com>
 v3->v4:
   change the patch title and commit message

 kernel/sched/core.c | 11 -----------
 kernel/sched/fair.c | 13 +++++++++++--
 2 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index da0bf6fe9ecd..2feff25fd905 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -9530,9 +9530,6 @@ 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_idle_mask);
-
 void __init sched_init(void)
 {
 	unsigned long ptr = 0;
@@ -9576,14 +9573,6 @@ 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_idle_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 77b2048a9326..61ae0853721e 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5843,8 +5843,8 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 #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_idle_mask);
+static DEFINE_PER_CPU(cpumask_var_t, load_balance_mask);
+static DEFINE_PER_CPU(cpumask_var_t, select_idle_mask);
 
 #ifdef CONFIG_NO_HZ_COMMON
 
@@ -11841,6 +11841,15 @@ 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_idle_mask, i),
+					GFP_KERNEL, cpu_to_node(i));
+	}
+
 	open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
 
 #ifdef CONFIG_NO_HZ_COMMON
-- 
2.25.1
Re: [PATCH v4] sched/fair: Make per-cpu cpumasks static
Posted by Vincent Guittot 3 years, 10 months ago 
On Wed, 6 Jul 2022 at 10:36, Bing Huang <huangbing775@126.com> wrote:
>
> From: Bing Huang <huangbing@kylinos.cn>
>
> load_balance_mask and select_idle_mask are only used in fair.c. Make

You have to rebase on tip/sched/core as select_idle_mask has been
renamed select_rq_mask

> 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()).
>
> Signed-off-by: Bing Huang <huangbing@kylinos.cn>
> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>

Beside the rebase and renaming

Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>

> ---
>
>  v1->v2:
>    move load_balance_mask and select_idle_mask allocation from
>    sched_init() to init_sched_fair_class()
>  v2->v3:
>    fixup by Dietmar Eggemann <dietmar.eggemann@arm.com>
>  v3->v4:
>    change the patch title and commit message
>
>  kernel/sched/core.c | 11 -----------
>  kernel/sched/fair.c | 13 +++++++++++--
>  2 files changed, 11 insertions(+), 13 deletions(-)
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index da0bf6fe9ecd..2feff25fd905 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -9530,9 +9530,6 @@ 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_idle_mask);
> -
>  void __init sched_init(void)
>  {
>         unsigned long ptr = 0;
> @@ -9576,14 +9573,6 @@ 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_idle_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 77b2048a9326..61ae0853721e 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -5843,8 +5843,8 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
>  #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_idle_mask);
> +static DEFINE_PER_CPU(cpumask_var_t, load_balance_mask);
> +static DEFINE_PER_CPU(cpumask_var_t, select_idle_mask);
>
>  #ifdef CONFIG_NO_HZ_COMMON
>
> @@ -11841,6 +11841,15 @@ 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_idle_mask, i),
> +                                       GFP_KERNEL, cpu_to_node(i));
> +       }
> +
>         open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
>
>  #ifdef CONFIG_NO_HZ_COMMON
> --
> 2.25.1
>

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