SMP: Allow smp_call_function_single() to current cpu

This removes the requirement for callers to get_cpu() to check in simple
cases.  This patch is for !CONFIG_SMP.

Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/include/linux/smp.h b/include/linux/smp.h
index 96ac21f8dd73..8039daced688 100644
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -7,6 +7,7 @@
  */
 
 #include <linux/errno.h>
+#include <asm/system.h>
 
 extern void cpu_idle(void);
 
@@ -102,7 +103,11 @@ static inline void smp_send_reschedule(int cpu) { }
 static inline int smp_call_function_single(int cpuid, void (*func) (void *info),
                                            void *info, int retry, int wait)
 {
-        return -EBUSY;
+        WARN_ON(cpuid != 0);
+        local_irq_disable();
+        func(info);
+        local_irq_enable();
+        return 0;
 }
 
 #endif /* !SMP */