#define CPU_ONLINE 0x0002 /* CPU (unsigned)v is up */
#define CPU_UP_PREPARE 0x0003 /* CPU (unsigned)v coming up */
-#define CPU_UP_CANCELED 0x0004 /* CPU (unsigned)v NOT coming up */
-#define CPU_DOWN_PREPARE 0x0005 /* CPU (unsigned)v going down */
-#define CPU_DOWN_FAILED 0x0006 /* CPU (unsigned)v NOT going down */
#define CPU_DEAD 0x0007 /* CPU (unsigned)v dead */
#define CPU_POST_DEAD 0x0009 /* CPU (unsigned)v dead, cpu_hotplug
* lock is dropped */
#ifdef CONFIG_SMP
extern bool cpuhp_tasks_frozen;
-/* Need to know about CPUs going up/down? */
-#if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
-#define cpu_notifier(fn, pri) { \
- static struct notifier_block fn##_nb = \
- { .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); \
-}
-
-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 /* #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)
-
-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)
-{
-}
-#endif
-
int cpu_up(unsigned int cpu);
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 cpuhp_tasks_frozen 0
-#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)
{
}
{
}
-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;
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)
void clear_tasks_mm_cpumask(int cpu);
int cpu_down(unsigned int cpu);
#define put_online_cpus() do { } while (0)
#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
CPUHP_POWERPC_MMU_CTX_PREPARE,
CPUHP_XEN_PREPARE,
CPUHP_XEN_EVTCHN_PREPARE,
- CPUHP_NOTIFY_PREPARE,
CPUHP_ARM_SHMOBILE_SCU_PREPARE,
CPUHP_SH_SH3X_PREPARE,
CPUHP_BLK_MQ_PREPARE,
CPUHP_KVM_PPC_BOOK3S_PREPARE,
CPUHP_ZCOMP_PREPARE,
CPUHP_TIMERS_DEAD,
- CPUHP_NOTF_ERR_INJ_PREPARE,
CPUHP_MIPS_SOC_PREPARE,
CPUHP_BRINGUP_CPU,
CPUHP_AP_IDLE_DEAD,
CPUHP_AP_PERF_ARM_L2X0_ONLINE,
CPUHP_AP_WORKQUEUE_ONLINE,
CPUHP_AP_RCUTREE_ONLINE,
- CPUHP_AP_NOTIFY_ONLINE,
CPUHP_AP_ONLINE_DYN,
CPUHP_AP_ONLINE_DYN_END = CPUHP_AP_ONLINE_DYN + 30,
CPUHP_AP_X86_HPET_ONLINE,
/*
* 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);
/* If set, cpu_up and cpu_down will return -EBUSY and do nothing.
* Should always be manipulated under cpu_add_remove_lock
EXPORT_SYMBOL_GPL(cpu_hotplug_enable);
#endif /* CONFIG_HOTPLUG_CPU */
-/* Need to know about CPUs going up/down? */
-int register_cpu_notifier(struct notifier_block *nb)
-{
- int ret;
- cpu_maps_update_begin();
- ret = raw_notifier_chain_register(&cpu_chain, nb);
- cpu_maps_update_done();
- return ret;
-}
-
-int __register_cpu_notifier(struct notifier_block *nb)
-{
- return raw_notifier_chain_register(&cpu_chain, nb);
-}
-
-static int __cpu_notify(unsigned long val, unsigned int cpu, int nr_to_call,
- int *nr_calls)
-{
- unsigned long mod = cpuhp_tasks_frozen ? CPU_TASKS_FROZEN : 0;
- void *hcpu = (void *)(long)cpu;
-
- int ret;
-
- ret = __raw_notifier_call_chain(&cpu_chain, val | mod, hcpu, nr_to_call,
- nr_calls);
-
- return notifier_to_errno(ret);
-}
-
-static int cpu_notify(unsigned long val, unsigned int cpu)
-{
- return __cpu_notify(val, cpu, -1, NULL);
-}
-
-static void cpu_notify_nofail(unsigned long val, unsigned int cpu)
-{
- BUG_ON(cpu_notify(val, cpu));
-}
-
/* Notifier wrappers for transitioning to state machine */
-static int notify_prepare(unsigned int cpu)
-{
- int nr_calls = 0;
- int ret;
-
- ret = __cpu_notify(CPU_UP_PREPARE, cpu, -1, &nr_calls);
- if (ret) {
- nr_calls--;
- printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n",
- __func__, cpu);
- __cpu_notify(CPU_UP_CANCELED, cpu, nr_calls, NULL);
- }
- return ret;
-}
-
-static int notify_online(unsigned int cpu)
-{
- cpu_notify(CPU_ONLINE, cpu);
- return 0;
-}
static int bringup_wait_for_ap(unsigned int cpu)
{
/* Arch-specific enabling code. */
ret = __cpu_up(cpu, idle);
irq_unlock_sparse();
- if (ret) {
- cpu_notify(CPU_UP_CANCELED, cpu);
+ if (ret)
return ret;
- }
ret = bringup_wait_for_ap(cpu);
BUG_ON(!cpu_online(cpu));
return ret;
BUG_ON(st->state < CPUHP_AP_ONLINE_IDLE);
undo_cpu_down(cpu, st);
- /*
- * This is a momentary workaround to keep the notifier users
- * happy. Will go away once we got rid of the notifiers.
- */
- cpu_notify_nofail(CPU_DOWN_FAILED, cpu);
st->rollback = false;
} else {
/* Cannot happen .... */
kthread_unpark(this_cpu_read(cpuhp_state.thread));
}
-EXPORT_SYMBOL(register_cpu_notifier);
-EXPORT_SYMBOL(__register_cpu_notifier);
-void unregister_cpu_notifier(struct notifier_block *nb)
-{
- cpu_maps_update_begin();
- raw_notifier_chain_unregister(&cpu_chain, nb);
- cpu_maps_update_done();
-}
-EXPORT_SYMBOL(unregister_cpu_notifier);
-
-void __unregister_cpu_notifier(struct notifier_block *nb)
-{
- raw_notifier_chain_unregister(&cpu_chain, nb);
-}
-EXPORT_SYMBOL(__unregister_cpu_notifier);
-
#ifdef CONFIG_HOTPLUG_CPU
/**
* clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU
read_unlock(&tasklist_lock);
}
-static int notify_down_prepare(unsigned int cpu)
-{
- int err, nr_calls = 0;
-
- err = __cpu_notify(CPU_DOWN_PREPARE, cpu, -1, &nr_calls);
- if (err) {
- nr_calls--;
- __cpu_notify(CPU_DOWN_FAILED, cpu, nr_calls, NULL);
- pr_warn("%s: attempt to take down CPU %u failed\n",
- __func__, cpu);
- }
- return err;
-}
-
/* Take this CPU down. */
static int take_cpu_down(void *_param)
{
return 0;
}
-static int notify_dead(unsigned int cpu)
-{
- cpu_notify_nofail(CPU_DEAD, cpu);
- check_for_tasks(cpu);
- return 0;
-}
-
static void cpuhp_complete_idle_dead(void *arg)
{
struct cpuhp_cpu_state *st = arg;
}
#else
-#define notify_down_prepare NULL
#define takedown_cpu NULL
-#define notify_dead NULL
#endif
#ifdef CONFIG_HOTPLUG_CPU
hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE;
out:
cpu_hotplug_done();
- /* This post dead nonsense must die */
- if (!ret && hasdied)
- cpu_notify_nofail(CPU_POST_DEAD, cpu);
return ret;
}
.startup.single = rcutree_prepare_cpu,
.teardown.single = rcutree_dead_cpu,
},
- /*
- * Preparatory and dead notifiers. Will be replaced once the notifiers
- * are converted to states.
- */
- [CPUHP_NOTIFY_PREPARE] = {
- .name = "notify:prepare",
- .startup.single = notify_prepare,
- .teardown.single = notify_dead,
- .skip_onerr = true,
- .cant_stop = true,
- },
/*
* On the tear-down path, timers_dead_cpu() must be invoked
* before blk_mq_queue_reinit_notify() from notify_dead(),
.startup.single = rcutree_online_cpu,
.teardown.single = rcutree_offline_cpu,
},
-
- /*
- * Online/down_prepare notifiers. Will be removed once the notifiers
- * are converted to states.
- */
- [CPUHP_AP_NOTIFY_ONLINE] = {
- .name = "notify:online",
- .startup.single = notify_online,
- .teardown.single = notify_down_prepare,
- .skip_onerr = true,
- },
#endif
/*
* The dynamically registered state space is here
Say N if unsure.
-config CPU_NOTIFIER_ERROR_INJECT
- tristate "CPU notifier error injection module"
- depends on HOTPLUG_CPU && NOTIFIER_ERROR_INJECTION
- help
- This option provides a kernel module that can be used to test
- the error handling of the cpu notifiers by injecting artificial
- errors to CPU notifier chain callbacks. It is controlled through
- debugfs interface under /sys/kernel/debug/notifier-error-inject/cpu
-
- If the notifier call chain should be failed with some events
- notified, write the error code to "actions/<notifier event>/error".
-
- Example: Inject CPU offline error (-1 == -EPERM)
-
- # cd /sys/kernel/debug/notifier-error-inject/cpu
- # echo -1 > actions/CPU_DOWN_PREPARE/error
- # echo 0 > /sys/devices/system/cpu/cpu1/online
- bash: echo: write error: Operation not permitted
-
- To compile this code as a module, choose M here: the module will
- be called cpu-notifier-error-inject.
-
- If unsure, say N.
-
config PM_NOTIFIER_ERROR_INJECT
tristate "PM notifier error injection module"
depends on PM && NOTIFIER_ERROR_INJECTION
obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o iommu-common.o
obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o
obj-$(CONFIG_NOTIFIER_ERROR_INJECTION) += notifier-error-inject.o
-obj-$(CONFIG_CPU_NOTIFIER_ERROR_INJECT) += cpu-notifier-error-inject.o
obj-$(CONFIG_PM_NOTIFIER_ERROR_INJECT) += pm-notifier-error-inject.o
obj-$(CONFIG_NETDEV_NOTIFIER_ERROR_INJECT) += netdev-notifier-error-inject.o
obj-$(CONFIG_MEMORY_NOTIFIER_ERROR_INJECT) += memory-notifier-error-inject.o
+++ /dev/null
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/cpu.h>
-
-#include "notifier-error-inject.h"
-
-static int priority;
-module_param(priority, int, 0);
-MODULE_PARM_DESC(priority, "specify cpu notifier priority");
-
-#define UP_PREPARE 0
-#define UP_PREPARE_FROZEN 0
-#define DOWN_PREPARE 0
-#define DOWN_PREPARE_FROZEN 0
-
-static struct notifier_err_inject cpu_notifier_err_inject = {
- .actions = {
- { NOTIFIER_ERR_INJECT_ACTION(UP_PREPARE) },
- { NOTIFIER_ERR_INJECT_ACTION(UP_PREPARE_FROZEN) },
- { NOTIFIER_ERR_INJECT_ACTION(DOWN_PREPARE) },
- { NOTIFIER_ERR_INJECT_ACTION(DOWN_PREPARE_FROZEN) },
- {}
- }
-};
-
-static int notf_err_handle(struct notifier_err_inject_action *action)
-{
- int ret;
-
- ret = action->error;
- if (ret)
- pr_info("Injecting error (%d) to %s\n", ret, action->name);
- return ret;
-}
-
-static int notf_err_inj_up_prepare(unsigned int cpu)
-{
- if (!cpuhp_tasks_frozen)
- return notf_err_handle(&cpu_notifier_err_inject.actions[0]);
- else
- return notf_err_handle(&cpu_notifier_err_inject.actions[1]);
-}
-
-static int notf_err_inj_dead(unsigned int cpu)
-{
- if (!cpuhp_tasks_frozen)
- return notf_err_handle(&cpu_notifier_err_inject.actions[2]);
- else
- return notf_err_handle(&cpu_notifier_err_inject.actions[3]);
-}
-
-static struct dentry *dir;
-
-static int err_inject_init(void)
-{
- int err;
-
- dir = notifier_err_inject_init("cpu", notifier_err_inject_dir,
- &cpu_notifier_err_inject, priority);
- if (IS_ERR(dir))
- return PTR_ERR(dir);
-
- err = cpuhp_setup_state_nocalls(CPUHP_NOTF_ERR_INJ_PREPARE,
- "cpu-err-notif:prepare",
- notf_err_inj_up_prepare,
- notf_err_inj_dead);
- if (err)
- debugfs_remove_recursive(dir);
-
- return err;
-}
-
-static void err_inject_exit(void)
-{
- cpuhp_remove_state_nocalls(CPUHP_NOTF_ERR_INJ_PREPARE);
- debugfs_remove_recursive(dir);
-}
-
-module_init(err_inject_init);
-module_exit(err_inject_exit);
-
-MODULE_DESCRIPTION("CPU notifier error injection module");
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");