diff options
Diffstat (limited to 'kernel/stop_machine.c')
| -rw-r--r-- | kernel/stop_machine.c | 44 | 
1 files changed, 22 insertions, 22 deletions
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index fd643d8c4b42..12484e5d5c88 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -35,13 +35,16 @@ struct cpu_stop_done {  /* the actual stopper, one per every possible cpu, enabled on online cpus */  struct cpu_stopper { +	struct task_struct	*thread; +  	spinlock_t		lock;  	bool			enabled;	/* is this stopper enabled? */  	struct list_head	works;		/* list of pending works */ + +	struct cpu_stop_work	stop_work;	/* for stop_cpus */  };  static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper); -static DEFINE_PER_CPU(struct task_struct *, cpu_stopper_task);  static bool stop_machine_initialized = false;  /* @@ -74,7 +77,6 @@ static void cpu_stop_signal_done(struct cpu_stop_done *done, bool executed)  static void cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work)  {  	struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); -	struct task_struct *p = per_cpu(cpu_stopper_task, cpu);  	unsigned long flags; @@ -82,7 +84,7 @@ static void cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work)  	if (stopper->enabled) {  		list_add_tail(&work->list, &stopper->works); -		wake_up_process(p); +		wake_up_process(stopper->thread);  	} else  		cpu_stop_signal_done(work->done, false); @@ -139,7 +141,7 @@ enum multi_stop_state {  };  struct multi_stop_data { -	int			(*fn)(void *); +	cpu_stop_fn_t		fn;  	void			*data;  	/* Like num_online_cpus(), but hotplug cpu uses us, so we need this. */  	unsigned int		num_threads; @@ -293,7 +295,6 @@ void stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,  /* static data for stop_cpus */  static DEFINE_MUTEX(stop_cpus_mutex); -static DEFINE_PER_CPU(struct cpu_stop_work, stop_cpus_work);  static void queue_stop_cpus_work(const struct cpumask *cpumask,  				 cpu_stop_fn_t fn, void *arg, @@ -302,22 +303,19 @@ static void queue_stop_cpus_work(const struct cpumask *cpumask,  	struct cpu_stop_work *work;  	unsigned int cpu; -	/* initialize works and done */ -	for_each_cpu(cpu, cpumask) { -		work = &per_cpu(stop_cpus_work, cpu); -		work->fn = fn; -		work->arg = arg; -		work->done = done; -	} -  	/*  	 * Disable preemption while queueing to avoid getting  	 * preempted by a stopper which might wait for other stoppers  	 * to enter @fn which can lead to deadlock.  	 */  	lg_global_lock(&stop_cpus_lock); -	for_each_cpu(cpu, cpumask) -		cpu_stop_queue_work(cpu, &per_cpu(stop_cpus_work, cpu)); +	for_each_cpu(cpu, cpumask) { +		work = &per_cpu(cpu_stopper.stop_work, cpu); +		work->fn = fn; +		work->arg = arg; +		work->done = done; +		cpu_stop_queue_work(cpu, work); +	}  	lg_global_unlock(&stop_cpus_lock);  } @@ -458,19 +456,21 @@ extern void sched_set_stop_task(int cpu, struct task_struct *stop);  static void cpu_stop_create(unsigned int cpu)  { -	sched_set_stop_task(cpu, per_cpu(cpu_stopper_task, cpu)); +	sched_set_stop_task(cpu, per_cpu(cpu_stopper.thread, cpu));  }  static void cpu_stop_park(unsigned int cpu)  {  	struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); -	struct cpu_stop_work *work; +	struct cpu_stop_work *work, *tmp;  	unsigned long flags;  	/* drain remaining works */  	spin_lock_irqsave(&stopper->lock, flags); -	list_for_each_entry(work, &stopper->works, list) +	list_for_each_entry_safe(work, tmp, &stopper->works, list) { +		list_del_init(&work->list);  		cpu_stop_signal_done(work->done, false); +	}  	stopper->enabled = false;  	spin_unlock_irqrestore(&stopper->lock, flags);  } @@ -485,7 +485,7 @@ static void cpu_stop_unpark(unsigned int cpu)  }  static struct smp_hotplug_thread cpu_stop_threads = { -	.store			= &cpu_stopper_task, +	.store			= &cpu_stopper.thread,  	.thread_should_run	= cpu_stop_should_run,  	.thread_fn		= cpu_stopper_thread,  	.thread_comm		= "migration/%u", @@ -515,7 +515,7 @@ early_initcall(cpu_stop_init);  #ifdef CONFIG_STOP_MACHINE -int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus) +static int __stop_machine(cpu_stop_fn_t fn, void *data, const struct cpumask *cpus)  {  	struct multi_stop_data msdata = {  		.fn = fn, @@ -548,7 +548,7 @@ int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus)  	return stop_cpus(cpu_online_mask, multi_cpu_stop, &msdata);  } -int stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus) +int stop_machine(cpu_stop_fn_t fn, void *data, const struct cpumask *cpus)  {  	int ret; @@ -582,7 +582,7 @@ EXPORT_SYMBOL_GPL(stop_machine);   * 0 if all executions of @fn returned 0, any non zero return value if any   * returned non zero.   */ -int stop_machine_from_inactive_cpu(int (*fn)(void *), void *data, +int stop_machine_from_inactive_cpu(cpu_stop_fn_t fn, void *data,  				  const struct cpumask *cpus)  {  	struct multi_stop_data msdata = { .fn = fn, .data = data,  |