diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 22ae91f8165f..33ac06c01458 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -232,4 +232,11 @@ static inline int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval) { return 0; extern bool cpu_mitigations_off(void); extern bool cpu_mitigations_auto_nosmt(void); +#define IDLE_START 1 +#define IDLE_END 2 + +void idle_notifier_register(struct notifier_block *n); +void idle_notifier_unregister(struct notifier_block *n); +void idle_notifier_call_chain(unsigned long val); + #endif /* _LINUX_CPU_H_ */ diff --git a/kernel/cpu.c b/kernel/cpu.c index d49ba9df8f06..e107dff94922 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -2913,3 +2913,23 @@ bool cpu_mitigations_auto_nosmt(void) return cpu_mitigations == CPU_MITIGATIONS_AUTO_NOSMT; } EXPORT_SYMBOL_GPL(cpu_mitigations_auto_nosmt); + +static ATOMIC_NOTIFIER_HEAD(idle_notifier); + +void idle_notifier_register(struct notifier_block *n) +{ + atomic_notifier_chain_register(&idle_notifier, n); +} +EXPORT_SYMBOL_GPL(idle_notifier_register); + +void idle_notifier_unregister(struct notifier_block *n) +{ + atomic_notifier_chain_unregister(&idle_notifier, n); +} +EXPORT_SYMBOL_GPL(idle_notifier_unregister); + +void idle_notifier_call_chain(unsigned long val) +{ + atomic_notifier_call_chain(&idle_notifier, val, NULL); +} +EXPORT_SYMBOL_GPL(idle_notifier_call_chain);