diff options
-rw-r--r-- | include/linux/cpu.h | 90 | ||||
-rw-r--r-- | include/linux/cpuhotplug.h | 3 | ||||
-rw-r--r-- | kernel/cpu.c | 139 | ||||
-rw-r--r-- | lib/Kconfig.debug | 24 | ||||
-rw-r--r-- | lib/Makefile | 1 | ||||
-rw-r--r-- | lib/cpu-notifier-error-inject.c | 84 |
6 files changed, 1 insertions, 340 deletions
diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 09807c2ce328..21f9c74496e7 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -57,9 +57,6 @@ struct notifier_block; #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 */ @@ -80,80 +77,14 @@ struct notifier_block; #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) { } @@ -162,14 +93,6 @@ 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; @@ -182,12 +105,6 @@ extern void get_online_cpus(void); 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); @@ -199,13 +116,6 @@ static inline void cpu_hotplug_done(void) {} #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 diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 175d276ac335..0d5ef8563113 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -59,7 +59,6 @@ enum cpuhp_state { 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, @@ -74,7 +73,6 @@ enum cpuhp_state { 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, @@ -145,7 +143,6 @@ enum cpuhp_state { 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, diff --git a/kernel/cpu.c b/kernel/cpu.c index 3ff0ea5db371..042fd7e8e030 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -183,23 +183,16 @@ EXPORT_SYMBOL_GPL(cpuhp_tasks_frozen); /* * 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 @@ -349,66 +342,7 @@ void cpu_hotplug_enable(void) 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) { @@ -433,10 +367,8 @@ static int bringup_cpu(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; @@ -565,11 +497,6 @@ static void cpuhp_thread_fun(unsigned int cpu) 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 .... */ @@ -659,22 +586,6 @@ void __init cpuhp_threads_init(void) 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 @@ -741,20 +652,6 @@ static inline void check_for_tasks(int dead_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) { @@ -833,13 +730,6 @@ static int takedown_cpu(unsigned int cpu) 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; @@ -863,9 +753,7 @@ void cpuhp_report_idle_dead(void) } #else -#define notify_down_prepare NULL #define takedown_cpu NULL -#define notify_dead NULL #endif #ifdef CONFIG_HOTPLUG_CPU @@ -924,9 +812,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen, 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; } @@ -1292,17 +1177,6 @@ static struct cpuhp_step cpuhp_bp_states[] = { .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(), * otherwise a RCU stall occurs. @@ -1391,17 +1265,6 @@ static struct cpuhp_step cpuhp_ap_states[] = { .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 diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index cb66a4648840..b06848a104e6 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1538,30 +1538,6 @@ config NOTIFIER_ERROR_INJECTION 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 diff --git a/lib/Makefile b/lib/Makefile index 50144a3aeebd..bc4073a8cd08 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -128,7 +128,6 @@ obj-$(CONFIG_SWIOTLB) += swiotlb.o obj-$(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 diff --git a/lib/cpu-notifier-error-inject.c b/lib/cpu-notifier-error-inject.c deleted file mode 100644 index 0e2c9a1e958a..000000000000 --- a/lib/cpu-notifier-error-inject.c +++ /dev/null @@ -1,84 +0,0 @@ -#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>"); |