Subsystems currently rely on static housekeeping masks determined at boot. Supporting runtime reconfiguration (DHEI) requires a mechanism to broadcast mask changes to affected kernel components.
Implement a blocking notifier chain for housekeeping mask updates. This infrastructure enables subsystems like genirq, workqueues, and RCU to react dynamically to isolation changes. Signed-off-by: Qiliang Yuan <[email protected]> --- include/linux/sched/isolation.h | 21 +++++++++++++++++++++ kernel/sched/isolation.c | 24 ++++++++++++++++++++++++ 2 files changed, 45 insertions(+) diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h index d8501f4709b58..9df55237d3901 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -5,6 +5,7 @@ #include <linux/cpuset.h> #include <linux/init.h> #include <linux/tick.h> +#include <linux/notifier.h> enum hk_type { HK_TYPE_DOMAIN, @@ -24,6 +25,13 @@ enum hk_type { HK_TYPE_KTHREAD = HK_TYPE_KERNEL_NOISE }; +struct housekeeping_update { + enum hk_type type; + const struct cpumask *new_mask; +}; + +#define HK_UPDATE_MASK 0x01 + #ifdef CONFIG_CPU_ISOLATION DECLARE_STATIC_KEY_FALSE(housekeeping_overridden); extern int housekeeping_any_cpu(enum hk_type type); @@ -33,6 +41,9 @@ extern void housekeeping_affine(struct task_struct *t, enum hk_type type); extern bool housekeeping_test_cpu(int cpu, enum hk_type type); extern void __init housekeeping_init(void); +extern int housekeeping_register_notifier(struct notifier_block *nb); +extern int housekeeping_unregister_notifier(struct notifier_block *nb); + #else static inline int housekeeping_any_cpu(enum hk_type type) @@ -59,6 +70,16 @@ static inline bool housekeeping_test_cpu(int cpu, enum hk_type type) } static inline void housekeeping_init(void) { } + +static inline int housekeeping_register_notifier(struct notifier_block *nb) +{ + return 0; +} + +static inline int housekeeping_unregister_notifier(struct notifier_block *nb) +{ + return 0; +} #endif /* CONFIG_CPU_ISOLATION */ static inline bool housekeeping_cpu(int cpu, enum hk_type type) diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c index 67a5ff273ea08..e7a21023726df 100644 --- a/kernel/sched/isolation.c +++ b/kernel/sched/isolation.c @@ -9,6 +9,7 @@ */ #include <linux/sched/isolation.h> #include <linux/mutex.h> +#include <linux/notifier.h> #include "sched.h" enum hk_flags { @@ -18,6 +19,7 @@ enum hk_flags { }; static DEFINE_MUTEX(housekeeping_mutex); +static BLOCKING_NOTIFIER_HEAD(housekeeping_notifier_list); DEFINE_STATIC_KEY_FALSE(housekeeping_overridden); EXPORT_SYMBOL_GPL(housekeeping_overridden); @@ -86,6 +88,28 @@ bool housekeeping_test_cpu(int cpu, enum hk_type type) } EXPORT_SYMBOL_GPL(housekeeping_test_cpu); +int housekeeping_register_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&housekeeping_notifier_list, nb); +} +EXPORT_SYMBOL_GPL(housekeeping_register_notifier); + +int housekeeping_unregister_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&housekeeping_notifier_list, nb); +} +EXPORT_SYMBOL_GPL(housekeeping_unregister_notifier); + +static int housekeeping_update_notify(enum hk_type type, const struct cpumask *new_mask) +{ + struct housekeeping_update update = { + .type = type, + .new_mask = new_mask, + }; + + return blocking_notifier_call_chain(&housekeeping_notifier_list, HK_UPDATE_MASK, &update); +} + void __init housekeeping_init(void) { enum hk_type type; -- 2.43.0
