#include "smpboot.h"
-#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
enum {
CSD_FLAG_LOCK = 0x01,
+ CSD_FLAG_WAIT = 0x02,
};
struct call_function_data {
struct call_single_data __percpu *csd;
cpumask_var_t cpumask;
- cpumask_var_t cpumask_ipi;
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_function_data, cfd_data);
-struct call_single_queue {
- struct list_head list;
- raw_spinlock_t lock;
-};
-
-static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_queue, call_single_queue);
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct llist_head, call_single_queue);
static int
hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
if (!zalloc_cpumask_var_node(&cfd->cpumask, GFP_KERNEL,
cpu_to_node(cpu)))
return notifier_from_errno(-ENOMEM);
- if (!zalloc_cpumask_var_node(&cfd->cpumask_ipi, GFP_KERNEL,
- cpu_to_node(cpu))) {
- free_cpumask_var(cfd->cpumask);
- return notifier_from_errno(-ENOMEM);
- }
cfd->csd = alloc_percpu(struct call_single_data);
if (!cfd->csd) {
- free_cpumask_var(cfd->cpumask_ipi);
free_cpumask_var(cfd->cpumask);
return notifier_from_errno(-ENOMEM);
}
case CPU_DEAD:
case CPU_DEAD_FROZEN:
free_cpumask_var(cfd->cpumask);
- free_cpumask_var(cfd->cpumask_ipi);
free_percpu(cfd->csd);
break;
#endif
void *cpu = (void *)(long)smp_processor_id();
int i;
- for_each_possible_cpu(i) {
- struct call_single_queue *q = &per_cpu(call_single_queue, i);
-
- raw_spin_lock_init(&q->lock);
- INIT_LIST_HEAD(&q->list);
- }
+ for_each_possible_cpu(i)
+ init_llist_head(&per_cpu(call_single_queue, i));
hotplug_cfd(&hotplug_cfd_notifier, CPU_UP_PREPARE, cpu);
register_cpu_notifier(&hotplug_cfd_notifier);
static void csd_unlock(struct call_single_data *csd)
{
- WARN_ON(!(csd->flags & CSD_FLAG_LOCK));
+ WARN_ON((csd->flags & CSD_FLAG_WAIT) && !(csd->flags & CSD_FLAG_LOCK));
/*
* ensure we're all done before releasing data:
* for execution on the given CPU. data must already have
* ->func, ->info, and ->flags set.
*/
-static
-void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
+static void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
{
- struct call_single_queue *dst = &per_cpu(call_single_queue, cpu);
- unsigned long flags;
- int ipi;
-
- raw_spin_lock_irqsave(&dst->lock, flags);
- ipi = list_empty(&dst->list);
- list_add_tail(&csd->list, &dst->list);
- raw_spin_unlock_irqrestore(&dst->lock, flags);
+ if (wait)
+ csd->flags |= CSD_FLAG_WAIT;
/*
* The list addition should be visible before sending the IPI
* locking and barrier primitives. Generic code isn't really
* equipped to do the right thing...
*/
- if (ipi)
+ if (llist_add(&csd->llist, &per_cpu(call_single_queue, cpu)))
arch_send_call_function_single_ipi(cpu);
if (wait)
*/
void generic_smp_call_function_single_interrupt(void)
{
- struct call_single_queue *q = &__get_cpu_var(call_single_queue);
- LIST_HEAD(list);
+ struct llist_node *entry, *next;
/*
* Shouldn't receive this interrupt on a cpu that is not yet online.
*/
WARN_ON_ONCE(!cpu_online(smp_processor_id()));
- raw_spin_lock(&q->lock);
- list_replace_init(&q->list, &list);
- raw_spin_unlock(&q->lock);
+ entry = llist_del_all(&__get_cpu_var(call_single_queue));
+ entry = llist_reverse_order(entry);
- while (!list_empty(&list)) {
+ while (entry) {
struct call_single_data *csd;
- csd = list_entry(list.next, struct call_single_data, list);
- list_del(&csd->list);
+ next = entry->next;
+ csd = llist_entry(entry, struct call_single_data, llist);
csd->func(csd->info);
-
csd_unlock(csd);
+
+ entry = next;
}
}
}
put_cpu();
}
+EXPORT_SYMBOL_GPL(__smp_call_function_single);
/**
* smp_call_function_many(): Run a function on a set of other CPUs.
if (unlikely(!cpumask_weight(cfd->cpumask)))
return;
- /*
- * After we put an entry into the list, cfd->cpumask may be cleared
- * again when another CPU sends another IPI for a SMP function call, so
- * cfd->cpumask will be zero.
- */
- cpumask_copy(cfd->cpumask_ipi, cfd->cpumask);
-
for_each_cpu(cpu, cfd->cpumask) {
struct call_single_data *csd = per_cpu_ptr(cfd->csd, cpu);
- struct call_single_queue *dst =
- &per_cpu(call_single_queue, cpu);
- unsigned long flags;
csd_lock(csd);
csd->func = func;
csd->info = info;
-
- raw_spin_lock_irqsave(&dst->lock, flags);
- list_add_tail(&csd->list, &dst->list);
- raw_spin_unlock_irqrestore(&dst->lock, flags);
+ llist_add(&csd->llist, &per_cpu(call_single_queue, cpu));
}
/* Send a message to all CPUs in the map */
- arch_send_call_function_ipi_mask(cfd->cpumask_ipi);
+ arch_send_call_function_ipi_mask(cfd->cpumask);
if (wait) {
for_each_cpu(cpu, cfd->cpumask) {
return 0;
}
EXPORT_SYMBOL(smp_call_function);
-#endif /* USE_GENERIC_SMP_HELPERS */
/* Setup configured maximum number of CPUs to activate */
unsigned int setup_max_cpus = NR_CPUS;
nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
}
+void __weak smp_announce(void)
+{
+ printk(KERN_INFO "Brought up %d CPUs\n", num_online_cpus());
+}
+
/* Called by boot processor to activate the rest. */
void __init smp_init(void)
{
}
/* Any cleanup work */
- printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
+ smp_announce();
smp_cpus_done(setup_max_cpus);
}
projects / cascardo / linux.git / blobdiff