diff --git a/xen/common/softirq.c b/xen/common/softirq.c
index bee4a82009..60f344e842 100644
--- a/xen/common/softirq.c
+++ b/xen/common/softirq.c
@@ -139,7 +139,9 @@ void cpu_raise_softirq_batch_finish(void)
 
 void raise_softirq(unsigned int nr)
 {
-    set_bit(nr, &softirq_pending(smp_processor_id()));
+    unsigned int cpu = smp_processor_id();
+
+    set_bit(nr, &softirq_pending(cpu));
 }
 
 /*