1 files changed, 18 insertions, 7 deletions

diff --git a/kernel/smp.c b/kernel/smp.c
index 75c970c715d3..12ed8b013e2d 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -267,7 +267,7 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
  *
  * Returns 0 on success, else a negative status code.
  */
-int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
+int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
                              int wait)
 {
         struct call_single_data d = {
@@ -336,7 +336,7 @@ EXPORT_SYMBOL(smp_call_function_single);
  *      3) any other online cpu in @mask
  */
 int smp_call_function_any(const struct cpumask *mask,
-                          void (*func)(void *info), void *info, int wait)
+                          smp_call_func_t func, void *info, int wait)
 {
         unsigned int cpu;
         const struct cpumask *nodemask;
@@ -365,9 +365,10 @@ call:
 EXPORT_SYMBOL_GPL(smp_call_function_any);
 
 /**
- * __smp_call_function_single(): Run a function on another CPU
+ * __smp_call_function_single(): Run a function on a specific CPU
  * @cpu: The CPU to run on.
  * @data: Pre-allocated and setup data structure
+ * @wait: If true, wait until function has completed on specified CPU.
  *
  * Like smp_call_function_single(), but allow caller to pass in a
  * pre-allocated data structure. Useful for embedding @data inside
@@ -376,8 +377,10 @@ EXPORT_SYMBOL_GPL(smp_call_function_any);
 void __smp_call_function_single(int cpu, struct call_single_data *data,
                                 int wait)
 {
-        csd_lock(data);
+        unsigned int this_cpu;
+        unsigned long flags;
 
+        this_cpu = get_cpu();
         /*
          * Can deadlock when called with interrupts disabled.
          * We allow cpu's that are not yet online though, as no one else can
@@ -387,7 +390,15 @@ void __smp_call_function_single(int cpu, struct call_single_data *data,
         WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled()
                      && !oops_in_progress);
 
-        generic_exec_single(cpu, data, wait);
+        if (cpu == this_cpu) {
+                local_irq_save(flags);
+                data->func(data->info);
+                local_irq_restore(flags);
+        } else {
+                csd_lock(data);
+                generic_exec_single(cpu, data, wait);
+        }
+        put_cpu();
 }
 
 /**
@@ -405,7 +416,7 @@ void __smp_call_function_single(int cpu, struct call_single_data *data,
  * must be disabled when calling this function.
  */
 void smp_call_function_many(const struct cpumask *mask,
-                            void (*func)(void *), void *info, bool wait)
+                            smp_call_func_t func, void *info, bool wait)
 {
         struct call_function_data *data;
         unsigned long flags;
@@ -489,7 +500,7 @@ EXPORT_SYMBOL(smp_call_function_many);
  * You must not call this function with disabled interrupts or from a
  * hardware interrupt handler or from a bottom half handler.
  */
-int smp_call_function(void (*func)(void *), void *info, int wait)
+int smp_call_function(smp_call_func_t func, void *info, int wait)
 {
         preempt_disable();
         smp_call_function_many(cpu_online_mask, func, info, wait);