[IA64] Allow smp_call_function_single() to current cpu

This removes the requirement for callers to get_cpu() to check in simple
cases.  i386 and x86_64 already received a similar treatment.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/kernel/smp.c

@@ -346,7 +346,7 @@ smp_flush_tlb_mm (struct mm_struct *mm)
 }
 
 /*
- * Run a function on another CPU
+ * Run a function on a specific CPU
  *  <func>	The function to run. This must be fast and non-blocking.
  *  <info>	An arbitrary pointer to pass to the function.
  *  <nonatomic>	Currently unused.
@@ -366,9 +366,11 @@ smp_call_function_single (int cpuid, void (*func) (void *info), void *info, int
 	int me = get_cpu(); /* prevent preemption and reschedule on another processor */
 
 	if (cpuid == me) {
-		printk(KERN_INFO "%s: trying to call self\n", __FUNCTION__);
+		local_irq_disable();
+		func(info);
+		local_irq_enable();
 		put_cpu();
-		return -EBUSY;
+		return 0;
 	}
 
 	data.func = func;