nohz.idle_cpus_mask is not required soon after early initialization since the boot CPU cannot go tickless idle before CPU is activated and tick is started.
Defer allocation of nohz.idle_cpus_mask to sched_init_smp() via init_sched_fair_class_smp(). This is preparation to convert nohz.idle_cpus_mask to sparsebitmap (sbm) which requires architectures to finish smp_prepare before initializing the core bits. No functional changes intended. Signed-off-by: K Prateek Nayak <[email protected]> --- kernel/sched/core.c | 2 ++ kernel/sched/fair.c | 8 +++++++- kernel/sched/sched.h | 1 + 3 files changed, 10 insertions(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 977f579da410..127aed81d316 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8849,6 +8849,8 @@ int sched_cpu_dying(unsigned int cpu) void __init sched_init_smp(void) { + init_sched_fair_class_smp(); + sched_init_numa(NUMA_NO_NODE); prandom_init_once(&sched_rnd_state); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 1c687c3c70f1..a0a659f4c3be 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -15645,6 +15645,13 @@ void show_numa_stats(struct task_struct *p, struct seq_file *m) } #endif /* CONFIG_NUMA_BALANCING */ +__init void init_sched_fair_class_smp(void) +{ +#ifdef CONFIG_NO_HZ_COMMON + zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); +#endif +} + __init void init_sched_fair_class(void) { int i; @@ -15666,6 +15673,5 @@ __init void init_sched_fair_class(void) #ifdef CONFIG_NO_HZ_COMMON nohz.next_balance = jiffies; nohz.next_blocked = jiffies; - zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); #endif } diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 7d2ec527b8a2..0726e8fb5967 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -3024,6 +3024,7 @@ extern void update_max_interval(void); extern void init_sched_dl_class(void); extern void init_sched_rt_class(void); extern void init_sched_fair_class(void); +extern void init_sched_fair_class_smp(void); extern void resched_curr(struct rq *rq); extern void resched_curr_lazy(struct rq *rq); -- 2.34.1
