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Diffstat (limited to 'kernel/smp.c')
-rw-r--r--kernel/smp.c35
1 files changed, 24 insertions, 11 deletions
diff --git a/kernel/smp.c b/kernel/smp.c
index 449b707fc20d..bd9f94028838 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -15,9 +15,9 @@
#include "smpboot.h"
-#ifdef CONFIG_USE_GENERIC_SMP_HELPERS
enum {
CSD_FLAG_LOCK = 0x01,
+ CSD_FLAG_WAIT = 0x02,
};
struct call_function_data {
@@ -48,10 +48,13 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
cpu_to_node(cpu)))
return notifier_from_errno(-ENOMEM);
if (!zalloc_cpumask_var_node(&cfd->cpumask_ipi, GFP_KERNEL,
- cpu_to_node(cpu)))
+ 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);
}
@@ -121,7 +124,7 @@ static void csd_lock(struct call_single_data *csd)
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:
@@ -136,13 +139,15 @@ static void csd_unlock(struct call_single_data *csd)
* 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;
+ if (wait)
+ csd->flags |= CSD_FLAG_WAIT;
+
raw_spin_lock_irqsave(&dst->lock, flags);
ipi = list_empty(&dst->list);
list_add_tail(&csd->list, &dst->list);
@@ -337,6 +342,7 @@ void __smp_call_function_single(int cpu, struct call_single_data *csd,
}
put_cpu();
}
+EXPORT_SYMBOL_GPL(__smp_call_function_single);
/**
* smp_call_function_many(): Run a function on a set of other CPUs.
@@ -456,7 +462,6 @@ int smp_call_function(smp_call_func_t func, void *info, int wait)
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;
@@ -521,6 +526,11 @@ void __init setup_nr_cpu_ids(void)
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)
{
@@ -537,7 +547,7 @@ 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);
}
@@ -572,8 +582,10 @@ EXPORT_SYMBOL(on_each_cpu);
*
* 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.
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler. The
+ * exception is that it may be used during early boot while
+ * early_boot_irqs_disabled is set.
*/
void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
void *info, bool wait)
@@ -582,9 +594,10 @@ void on_each_cpu_mask(const struct cpumask *mask, smp_call_func_t func,
smp_call_function_many(mask, func, info, wait);
if (cpumask_test_cpu(cpu, mask)) {
- local_irq_disable();
+ unsigned long flags;
+ local_irq_save(flags);
func(info);
- local_irq_enable();
+ local_irq_restore(flags);
}
put_cpu();
}