diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 92f9fcdc5be..4f88b0698a9 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -121,26 +121,46 @@ enum { { .notifier_call = fn, .priority = pri }; \ register_cpu_notifier(&fn##_nb); \ } + +#define __cpu_notifier(fn, pri) { \ + static struct notifier_block fn##_nb = \ + { .notifier_call = fn, .priority = pri }; \ + __register_cpu_notifier(&fn##_nb); \ +} #else /* #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) +#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) #endif /* #else #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE) */ + #ifdef CONFIG_HOTPLUG_CPU extern int register_cpu_notifier(struct notifier_block *nb); +extern int __register_cpu_notifier(struct notifier_block *nb); extern void unregister_cpu_notifier(struct notifier_block *nb); +extern void __unregister_cpu_notifier(struct notifier_block *nb); #else #ifndef MODULE extern int register_cpu_notifier(struct notifier_block *nb); +extern int __register_cpu_notifier(struct notifier_block *nb); #else static inline int register_cpu_notifier(struct notifier_block *nb) { return 0; } + +static inline int __register_cpu_notifier(struct notifier_block *nb) +{ + return 0; +} #endif static inline void unregister_cpu_notifier(struct notifier_block *nb) { } + +static inline void __unregister_cpu_notifier(struct notifier_block *nb) +{ +} #endif int cpu_up(unsigned int cpu); @@ -148,19 +168,32 @@ void notify_cpu_starting(unsigned int cpu); extern void cpu_maps_update_begin(void); extern void cpu_maps_update_done(void); +#define cpu_notifier_register_begin cpu_maps_update_begin +#define cpu_notifier_register_done cpu_maps_update_done + #else /* CONFIG_SMP */ #define cpu_notifier(fn, pri) do { (void)(fn); } while (0) +#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0) static inline int register_cpu_notifier(struct notifier_block *nb) { return 0; } +static inline int __register_cpu_notifier(struct notifier_block *nb) +{ + return 0; +} + static inline void unregister_cpu_notifier(struct notifier_block *nb) { } +static inline void __unregister_cpu_notifier(struct notifier_block *nb) +{ +} + static inline void cpu_maps_update_begin(void) { } @@ -169,6 +202,14 @@ static inline void cpu_maps_update_done(void) { } +static inline void cpu_notifier_register_begin(void) +{ +} + +static inline void cpu_notifier_register_done(void) +{ +} + #endif /* CONFIG_SMP */ extern struct bus_type cpu_subsys; @@ -180,8 +221,11 @@ extern void put_online_cpus(void); extern void cpu_hotplug_disable(void); extern void cpu_hotplug_enable(void); #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) +#define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri) #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) +#define __register_hotcpu_notifier(nb) __register_cpu_notifier(nb) #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb) +#define __unregister_hotcpu_notifier(nb) __unregister_cpu_notifier(nb) int cpu_down(unsigned int cpu); #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE @@ -204,9 +248,12 @@ static inline void cpu_hotplug_driver_unlock(void) #define cpu_hotplug_disable() do { } while (0) #define cpu_hotplug_enable() do { } while (0) #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) +#define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) /* These aren't inline functions due to a GCC bug. */ #define register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) +#define __register_hotcpu_notifier(nb) ({ (void)(nb); 0; }) #define unregister_hotcpu_notifier(nb) ({ (void)(nb); }) +#define __unregister_hotcpu_notifier(nb) ({ (void)(nb); }) #endif /* CONFIG_HOTPLUG_CPU */ #ifdef CONFIG_PM_SLEEP_SMP diff --git a/kernel/cpu.c b/kernel/cpu.c index 02caf610cc9..677b4619ea9 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -24,18 +24,23 @@ static DEFINE_MUTEX(cpu_add_remove_lock); /* - * The following two API's must be used when attempting - * to serialize the updates to cpu_online_mask, cpu_present_mask. + * The following two APIs (cpu_maps_update_begin/done) must be used when + * attempting to serialize the updates to cpu_online_mask & cpu_present_mask. + * The APIs cpu_notifier_register_begin/done() must be used to protect CPU + * hotplug callback (un)registration performed using __register_cpu_notifier() + * or __unregister_cpu_notifier(). */ void cpu_maps_update_begin(void) { mutex_lock(&cpu_add_remove_lock); } +EXPORT_SYMBOL(cpu_notifier_register_begin); void cpu_maps_update_done(void) { mutex_unlock(&cpu_add_remove_lock); } +EXPORT_SYMBOL(cpu_notifier_register_done); static RAW_NOTIFIER_HEAD(cpu_chain); @@ -166,6 +171,11 @@ int __ref register_cpu_notifier(struct notifier_block *nb) return ret; } +int __ref __register_cpu_notifier(struct notifier_block *nb) +{ + return raw_notifier_chain_register(&cpu_chain, nb); +} + static int __cpu_notify(unsigned long val, void *v, int nr_to_call, int *nr_calls) { @@ -189,6 +199,7 @@ static void cpu_notify_nofail(unsigned long val, void *v) BUG_ON(cpu_notify(val, v)); } EXPORT_SYMBOL(register_cpu_notifier); +EXPORT_SYMBOL(__register_cpu_notifier); void __ref unregister_cpu_notifier(struct notifier_block *nb) { @@ -198,6 +209,12 @@ void __ref unregister_cpu_notifier(struct notifier_block *nb) } EXPORT_SYMBOL(unregister_cpu_notifier); +void __ref __unregister_cpu_notifier(struct notifier_block *nb) +{ + raw_notifier_chain_unregister(&cpu_chain, nb); +} +EXPORT_SYMBOL(__unregister_cpu_notifier); + static inline void check_for_tasks(int cpu) { struct task_struct *p;