diff options
Diffstat (limited to 'kernel/cpu.c')
| -rw-r--r-- | kernel/cpu.c | 42 |
1 files changed, 25 insertions, 17 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index f6e726f1849..12b7458f23b 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -126,7 +126,7 @@ static void cpu_hotplug_done(void) #else /* #if CONFIG_HOTPLUG_CPU */ static void cpu_hotplug_begin(void) {} static void cpu_hotplug_done(void) {} -#endif /* #esle #if CONFIG_HOTPLUG_CPU */ +#endif /* #else #if CONFIG_HOTPLUG_CPU */ /* Need to know about CPUs going up/down? */ int __ref register_cpu_notifier(struct notifier_block *nb) @@ -160,7 +160,6 @@ static void cpu_notify_nofail(unsigned long val, void *v) { BUG_ON(cpu_notify(val, v)); } - EXPORT_SYMBOL(register_cpu_notifier); void __ref unregister_cpu_notifier(struct notifier_block *nb) @@ -189,7 +188,6 @@ static inline void check_for_tasks(int cpu) } struct take_cpu_down_param { - struct task_struct *caller; unsigned long mod; void *hcpu; }; @@ -198,7 +196,6 @@ struct take_cpu_down_param { static int __ref take_cpu_down(void *_param) { struct take_cpu_down_param *param = _param; - unsigned int cpu = (unsigned long)param->hcpu; int err; /* Ensure this CPU doesn't handle any more interrupts. */ @@ -207,12 +204,6 @@ static int __ref take_cpu_down(void *_param) return err; cpu_notify(CPU_DYING | param->mod, param->hcpu); - - if (task_cpu(param->caller) == cpu) - move_task_off_dead_cpu(cpu, param->caller); - /* Force idle task to run as soon as we yield: it should - immediately notice cpu is offline and die quickly. */ - sched_idle_next(); return 0; } @@ -223,7 +214,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) void *hcpu = (void *)(long)cpu; unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; struct take_cpu_down_param tcd_param = { - .caller = current, .mod = mod, .hcpu = hcpu, }; @@ -235,6 +225,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) return -EINVAL; cpu_hotplug_begin(); + err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls); if (err) { nr_calls--; @@ -253,9 +244,15 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) } BUG_ON(cpu_online(cpu)); - /* Wait for it to sleep (leaving idle task). */ + /* + * The migration_call() CPU_DYING callback will have removed all + * runnable tasks from the cpu, there's only the idle task left now + * that the migration thread is done doing the stop_machine thing. + * + * Wait for the stop thread to go away. + */ while (!idle_cpu(cpu)) - yield(); + cpu_relax(); /* This actually kills the CPU. */ __cpu_die(cpu); @@ -306,7 +303,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls); if (ret) { nr_calls--; - printk("%s: attempt to bring up CPU %u failed\n", + printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n", __func__, cpu); goto out_notify; } @@ -386,6 +383,14 @@ out: #ifdef CONFIG_PM_SLEEP_SMP static cpumask_var_t frozen_cpus; +void __weak arch_disable_nonboot_cpus_begin(void) +{ +} + +void __weak arch_disable_nonboot_cpus_end(void) +{ +} + int disable_nonboot_cpus(void) { int cpu, first_cpu, error = 0; @@ -397,6 +402,7 @@ int disable_nonboot_cpus(void) * with the userspace trying to use the CPU hotplug at the same time */ cpumask_clear(frozen_cpus); + arch_disable_nonboot_cpus_begin(); printk("Disabling non-boot CPUs ...\n"); for_each_online_cpu(cpu) { @@ -412,6 +418,8 @@ int disable_nonboot_cpus(void) } } + arch_disable_nonboot_cpus_end(); + if (!error) { BUG_ON(num_online_cpus() > 1); /* Make sure the CPUs won't be enabled by someone else */ @@ -441,14 +449,14 @@ void __ref enable_nonboot_cpus(void) if (cpumask_empty(frozen_cpus)) goto out; - printk("Enabling non-boot CPUs ...\n"); + printk(KERN_INFO "Enabling non-boot CPUs ...\n"); arch_enable_nonboot_cpus_begin(); for_each_cpu(cpu, frozen_cpus) { error = _cpu_up(cpu, 1); if (!error) { - printk("CPU%d is up\n", cpu); + printk(KERN_INFO "CPU%d is up\n", cpu); continue; } printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error); @@ -500,7 +508,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu) */ /* cpu_bit_bitmap[0] is empty - so we can back into it */ -#define MASK_DECLARE_1(x) [x+1][0] = 1UL << (x) +#define MASK_DECLARE_1(x) [x+1][0] = (1UL << (x)) #define MASK_DECLARE_2(x) MASK_DECLARE_1(x), MASK_DECLARE_1(x+1) #define MASK_DECLARE_4(x) MASK_DECLARE_2(x), MASK_DECLARE_2(x+2) #define MASK_DECLARE_8(x) MASK_DECLARE_4(x), MASK_DECLARE_4(x+4) |