diff --git a/tools/virtio/linux/kernel.h b/tools/virtio/linux/kernel.h
index 7ef45a4a3cba..6683b4a70b05 100644
--- a/tools/virtio/linux/kernel.h
+++ b/tools/virtio/linux/kernel.h
@@ -127,7 +127,7 @@ static inline void free_page(unsigned long addr)
 #define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 #define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
 
-#define WARN_ON_ONCE(cond) ((cond) ? fprintf (stderr, "WARNING\n") : 0)
+#define WARN_ON_ONCE(cond) (unlikely(cond) ? fprintf (stderr, "WARNING\n") : 0)
 
 #define min(x, y) ({				\
 	typeof(x) _min1 = (x);			\