No need for an extra notifier. We don't need to handle all these states. It's sufficient to kill the timer when the cpu dies. Signed-off-by: Thomas Gleixner --- kernel/sched/core.c | 34 +--------------------------------- 1 file changed, 1 insertion(+), 33 deletions(-) Index: b/kernel/sched/core.c =================================================================== --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -381,29 +381,6 @@ void hrtick_start(struct rq *rq, u64 del } } -static int -hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu) -{ - int cpu = (int)(long)hcpu; - - switch (action) { - case CPU_UP_CANCELED: - case CPU_UP_CANCELED_FROZEN: - case CPU_DOWN_PREPARE: - case CPU_DOWN_PREPARE_FROZEN: - case CPU_DEAD: - case CPU_DEAD_FROZEN: - hrtick_clear(cpu_rq(cpu)); - return NOTIFY_OK; - } - - return NOTIFY_DONE; -} - -static __init void init_hrtick(void) -{ - hotcpu_notifier(hotplug_hrtick, 0); -} #else /* * Called to set the hrtick timer state. @@ -420,10 +397,6 @@ void hrtick_start(struct rq *rq, u64 del hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay), HRTIMER_MODE_REL_PINNED); } - -static inline void init_hrtick(void) -{ -} #endif /* CONFIG_SMP */ static void init_rq_hrtick(struct rq *rq) @@ -447,10 +420,6 @@ static inline void hrtick_clear(struct r static inline void init_rq_hrtick(struct rq *rq) { } - -static inline void init_hrtick(void) -{ -} #endif /* CONFIG_SCHED_HRTICK */ /* @@ -7364,6 +7333,7 @@ int sched_cpu_dying(unsigned int cpu) calc_load_migrate(rq); update_max_interval(); nohz_balance_exit_idle(cpu); + hrtick_clear(rq); return 0; } @@ -7388,8 +7358,6 @@ void __init sched_init_smp(void) cpumask_set_cpu(smp_processor_id(), non_isolated_cpus); mutex_unlock(&sched_domains_mutex); - init_hrtick(); - /* Move init over to a non-isolated CPU */ if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0) BUG();