diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h index ed935ffc6ffa..194c586fbb12 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -6,6 +6,7 @@ #include #ifdef CONFIG_NO_HZ_FULL +DECLARE_STATIC_KEY_FALSE(housekeeping_overriden); extern int housekeeping_any_cpu(void); extern const struct cpumask *housekeeping_cpumask(void); extern void housekeeping_affine(struct task_struct *t); @@ -31,7 +32,7 @@ static inline void housekeeping_init(void) { } static inline bool is_housekeeping_cpu(int cpu) { #ifdef CONFIG_NO_HZ_FULL - if (tick_nohz_full_enabled()) + if (static_branch_unlikely(&housekeeping_overriden)) return housekeeping_test_cpu(cpu); #endif return true; diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c index 16445097eb25..bb8ba19a0235 100644 --- a/kernel/sched/isolation.c +++ b/kernel/sched/isolation.c @@ -10,12 +10,15 @@ #include #include #include +#include +DEFINE_STATIC_KEY_FALSE(housekeeping_overriden); +EXPORT_SYMBOL_GPL(housekeeping_overriden); static cpumask_var_t housekeeping_mask; int housekeeping_any_cpu(void) { - if (tick_nohz_full_enabled()) + if (static_branch_unlikely(&housekeeping_overriden)) return cpumask_any_and(housekeeping_mask, cpu_online_mask); return smp_processor_id(); @@ -24,7 +27,7 @@ EXPORT_SYMBOL_GPL(housekeeping_any_cpu); const struct cpumask *housekeeping_cpumask(void) { - if (tick_nohz_full_enabled()) + if (static_branch_unlikely(&housekeeping_overriden)) return housekeeping_mask; return cpu_possible_mask; @@ -33,14 +36,14 @@ EXPORT_SYMBOL_GPL(housekeeping_cpumask); void housekeeping_affine(struct task_struct *t) { - if (tick_nohz_full_enabled()) + if (static_branch_unlikely(&housekeeping_overriden)) set_cpus_allowed_ptr(t, housekeeping_mask); } EXPORT_SYMBOL_GPL(housekeeping_affine); bool housekeeping_test_cpu(int cpu) { - if (tick_nohz_full_enabled()) + if (static_branch_unlikely(&housekeeping_overriden)) return cpumask_test_cpu(cpu, housekeeping_mask); return true; @@ -62,6 +65,8 @@ void __init housekeeping_init(void) cpumask_andnot(housekeeping_mask, cpu_possible_mask, tick_nohz_full_mask); + static_branch_enable(&housekeeping_overriden); + /* We need at least one CPU to handle housekeeping work */ WARN_ON_ONCE(cpumask_empty(housekeeping_mask)); }