diff options
Diffstat (limited to 'kernel/smp.c')
| -rw-r--r-- | kernel/smp.c | 91 |
1 files changed, 65 insertions, 26 deletions
diff --git a/kernel/smp.c b/kernel/smp.c index c9d1c78..f104084 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -16,11 +16,11 @@ static DEFINE_PER_CPU(struct call_single_queue, call_single_queue); static struct { struct list_head queue; - spinlock_t lock; + raw_spinlock_t lock; } call_function __cacheline_aligned_in_smp = { .queue = LIST_HEAD_INIT(call_function.queue), - .lock = __SPIN_LOCK_UNLOCKED(call_function.lock), + .lock = __RAW_SPIN_LOCK_UNLOCKED(call_function.lock), }; enum { @@ -35,7 +35,7 @@ struct call_function_data { struct call_single_queue { struct list_head list; - spinlock_t lock; + raw_spinlock_t lock; }; static DEFINE_PER_CPU(struct call_function_data, cfd_data); @@ -80,7 +80,7 @@ static int __cpuinit init_call_single_data(void) for_each_possible_cpu(i) { struct call_single_queue *q = &per_cpu(call_single_queue, i); - spin_lock_init(&q->lock); + raw_spin_lock_init(&q->lock); INIT_LIST_HEAD(&q->list); } @@ -141,10 +141,10 @@ void generic_exec_single(int cpu, struct call_single_data *data, int wait) unsigned long flags; int ipi; - spin_lock_irqsave(&dst->lock, flags); + raw_spin_lock_irqsave(&dst->lock, flags); ipi = list_empty(&dst->list); list_add_tail(&data->list, &dst->list); - spin_unlock_irqrestore(&dst->lock, flags); + raw_spin_unlock_irqrestore(&dst->lock, flags); /* * The list addition should be visible before sending the IPI @@ -171,7 +171,7 @@ void generic_exec_single(int cpu, struct call_single_data *data, int wait) void generic_smp_call_function_interrupt(void) { struct call_function_data *data; - int cpu = get_cpu(); + int cpu = smp_processor_id(); /* * Shouldn't receive this interrupt on a cpu that is not yet online. @@ -201,9 +201,9 @@ void generic_smp_call_function_interrupt(void) refs = atomic_dec_return(&data->refs); WARN_ON(refs < 0); if (!refs) { - spin_lock(&call_function.lock); + raw_spin_lock(&call_function.lock); list_del_rcu(&data->csd.list); - spin_unlock(&call_function.lock); + raw_spin_unlock(&call_function.lock); } if (refs) @@ -212,7 +212,6 @@ void generic_smp_call_function_interrupt(void) csd_unlock(&data->csd); } - put_cpu(); } /* @@ -230,9 +229,9 @@ void generic_smp_call_function_single_interrupt(void) */ WARN_ON_ONCE(!cpu_online(smp_processor_id())); - spin_lock(&q->lock); + raw_spin_lock(&q->lock); list_replace_init(&q->list, &list); - spin_unlock(&q->lock); + raw_spin_unlock(&q->lock); while (!list_empty(&list)) { struct call_single_data *data; @@ -265,9 +264,7 @@ static DEFINE_PER_CPU(struct call_single_data, csd_data); * @info: An arbitrary pointer to pass to the function. * @wait: If true, wait until function has completed on other CPUs. * - * Returns 0 on success, else a negative status code. Note that @wait - * will be implicitly turned on in case of allocation failures, since - * we fall back to on-stack allocation. + * Returns 0 on success, else a negative status code. */ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, int wait) @@ -321,6 +318,51 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, } EXPORT_SYMBOL(smp_call_function_single); +/* + * smp_call_function_any - Run a function on any of the given cpus + * @mask: The mask of cpus it can run on. + * @func: The function to run. This must be fast and non-blocking. + * @info: An arbitrary pointer to pass to the function. + * @wait: If true, wait until function has completed. + * + * Returns 0 on success, else a negative status code (if no cpus were online). + * Note that @wait will be implicitly turned on in case of allocation failures, + * since we fall back to on-stack allocation. + * + * Selection preference: + * 1) current cpu if in @mask + * 2) any cpu of current node if in @mask + * 3) any other online cpu in @mask + */ +int smp_call_function_any(const struct cpumask *mask, + void (*func)(void *info), void *info, int wait) +{ + unsigned int cpu; + const struct cpumask *nodemask; + int ret; + + /* Try for same CPU (cheapest) */ + cpu = get_cpu(); + if (cpumask_test_cpu(cpu, mask)) + goto call; + + /* Try for same node. */ + nodemask = cpumask_of_node(cpu_to_node(cpu)); + for (cpu = cpumask_first_and(nodemask, mask); cpu < nr_cpu_ids; + cpu = cpumask_next_and(cpu, nodemask, mask)) { + if (cpu_online(cpu)) + goto call; + } + + /* Any online will do: smp_call_function_single handles nr_cpu_ids. */ + cpu = cpumask_any_and(mask, cpu_online_mask); +call: + ret = smp_call_function_single(cpu, func, info, wait); + put_cpu(); + return ret; +} +EXPORT_SYMBOL_GPL(smp_call_function_any); + /** * __smp_call_function_single(): Run a function on another CPU * @cpu: The CPU to run on. @@ -355,9 +397,7 @@ void __smp_call_function_single(int cpu, struct call_single_data *data, * @wait: If true, wait (atomically) until function has completed * on other CPUs. * - * If @wait is true, then returns once @func has returned. Note that @wait - * will be implicitly turned on in case of allocation failures, since - * we fall back to on-stack allocation. + * If @wait is true, then returns once @func has returned. * * You must not call this function with disabled interrupts or from a * hardware interrupt handler or from a bottom half handler. Preemption @@ -408,14 +448,14 @@ void smp_call_function_many(const struct cpumask *mask, cpumask_clear_cpu(this_cpu, data->cpumask); atomic_set(&data->refs, cpumask_weight(data->cpumask)); - spin_lock_irqsave(&call_function.lock, flags); + raw_spin_lock_irqsave(&call_function.lock, flags); /* * Place entry at the _HEAD_ of the list, so that any cpu still * observing the entry in generic_smp_call_function_interrupt() * will not miss any other list entries: */ list_add_rcu(&data->csd.list, &call_function.queue); - spin_unlock_irqrestore(&call_function.lock, flags); + raw_spin_unlock_irqrestore(&call_function.lock, flags); /* * Make the list addition visible before sending the ipi. @@ -443,8 +483,7 @@ EXPORT_SYMBOL(smp_call_function_many); * Returns 0. * * If @wait is true, then returns once @func has returned; otherwise - * it returns just before the target cpu calls @func. In case of allocation - * failure, @wait will be implicitly turned on. + * it returns just before the target cpu calls @func. * * You must not call this function with disabled interrupts or from a * hardware interrupt handler or from a bottom half handler. @@ -461,20 +500,20 @@ EXPORT_SYMBOL(smp_call_function); void ipi_call_lock(void) { - spin_lock(&call_function.lock); + raw_spin_lock(&call_function.lock); } void ipi_call_unlock(void) { - spin_unlock(&call_function.lock); + raw_spin_unlock(&call_function.lock); } void ipi_call_lock_irq(void) { - spin_lock_irq(&call_function.lock); + raw_spin_lock_irq(&call_function.lock); } void ipi_call_unlock_irq(void) { - spin_unlock_irq(&call_function.lock); + raw_spin_unlock_irq(&call_function.lock); } |
